arXiv daily: High Energy Physics - Phenomenology

arXiv daily: High Energy Physics - Phenomenology (hep-ph)

1.Analysis of final state lepton polarization-dependent observables in $H\to \ell^{+}\ell^{-} γ$ in the SM at loop level

Authors:Ishtiaq Ahmed, Usman Hasan, Shahin Iqbal, M. Junaid, Bilal Tariq, A. Uzair

Abstract: Recently, the CMS and ATLAS collaborations have announced the results for $H\rightarrow Z[\rightarrow \ell^{+}\ell^{-}]\gamma$ with $\ell=e$ or $\mu$, where $H\rightarrow Z\gamma$ is a sub-process of $H\rightarrow \ell^{+} \ell^{-} \gamma$. This semi-leptonic Higgs decay receives loop induced resonant $H\rightarrow Z[\rightarrow \ell^{+}\ell^{-}]\gamma$ as well as non-resonant contributions as discussed in. To probe further features coming from these contributions to $H\rightarrow \ell^{+} \ell^{-} \gamma$, we suggest that the polarization of the final state lepton is an important parameter. We show that the resonant and non-resonant cross-terms play an important role when the polarization of final state lepton is taken into account, which is negligible in the case of un-polarized leptons. For this purpose, we have calculated the polarized decay rates and the longitudinal, normal and transverse polarization asymmetries. We find that these asymmetries purely come from the loop contributions and are helpful to further investigate the resonant and non-resonant nature of $H\rightarrow Z[\rightarrow \ell^{+}\ell^{-}]\gamma$ decay. We observe that for $\ell=e,\mu$, the longitudinal decay rate is highly suppressed around $m_{\ell\ell}\approx 60$GeV when the final lepton spin is $-\frac{1}{2}$, dramatically increasing the corresponding lepton polarization asymmetries. Furthermore, we analyze another clean observable, the ratio of decay rates $\Gamma$, $R^{\ell\ell'}\equiv \frac{\Gamma_{H\rightarrow \ell^{+} \ell^{-} \gamma}}{\Gamma_{H\rightarrow \ell^{'+} \ell^{'-} \gamma}}$, where $\ell$ and $\ell'$ refer to different final state lepton generations. Therefore, the precise measurements of these observables at CMS and ATLAS can provide a fertile ground to test not only the Standard Model (SM) but also to examine the signatures of possible new physics (NP) beyond the SM.

2.The muon parton distribution functions

Authors:Stefano Frixione, Giovanni Stagnitto

Abstract: We compute the Parton Distribution Functions (PDFs) of the unpolarised muon for the leptons, the photon, the light quarks, and the gluon. We discuss in detail the issues stemming from the necessity of evaluating the strong coupling constant at scales of the order of the typical hadron mass, and compare our novel approach with those currently available in the literature. While we restrict our phenomenological results to be leading-logarithmic accurate, we set up our formalism in a way that renders it straightforward to achieve next-to-leading logarithmic accuracy in the QED, QCD, and mixed QED$\times$QCD contributions.

3.High-energy resummation in Higgs production at the next-to-leading order

Authors:Francesco Giovanni Celiberto, Michael Fucilla, Dmitry Yu. Ivanov, Mohammed M. A. Mohammed, Alessandro Papa

Abstract: We present the full next-to-leading order (NLO) result for the impact factor of a forward Higgs boson, obtained in the infinite-top-mass limit, both in the momentum representation and as superposition of the eigenfunctions of the leading-order (LO) BFKL kernel.

4.Search For a Leptoquark and Vector-like Lepton in a Muon Collider

Authors:Nivedita Ghosh, Santosh Kumar Rai, Tousik Samui

Abstract: The proposal for a high-energy muon collider offers many opportunities in the search for physics beyond the Standard Model (BSM). The collider by construction is likely to be more sensitive to the muon-philic models, primarily motivated by the BSM explanation of muon $(g-2)$ excess and quark flavor anomalies. In this work, we explore the potential of the proposed muon collider in the context of such models and focus on one such model that extends the Standard Model (SM) with a leptoquark, a vector-like lepton, and a real scalar. In this model, we propose searches for TeV scale leptoquarks in $2\mu+2b+$MET channel. Notably, the leptoquark can be produced singly at the muon collider with a large cross-section. We have shown that a significant signal in this channel can be detected at 3~TeV muon collider even with an integrated luminosity as low as $\sim 10$~fb$^{-1}$.

5.First determination of the Jarlskog invariant of CP violation from the moduli of the CKM matrix elements

Authors:Shu Luo, Zhi-zhong Xing

Abstract: We find that the precision and accuracy of current experimental data on the moduli of nine Cabibbo-Kobayashi-Maskawa (CKM) quark flavor mixing matrix elements allows us to numerically determine the correct size of the Jarlskog invariant of CP violation from four of them in eight different ways for the first time. This observation implies a remarkable self-consistency of the correlation between CP-conserving and CP-violating quantities of the CKM matrix as guaranteed by its unitarity.

6.Double charmed meson production in $pp$ and $pA$ collisions at the LHC within the dipole approach in momentum representation

Authors:G. Sampaio dos Santos, G. Gil da Silveira, M. V. T. Machado

Abstract: A study of double charmed meson production in proton-proton and proton-nucleus collisions at the LHC energies is performed. Based on the color dipole formalism developed in the transverse momentum representation and the double parton scattering mechanism, predictions are made for the transverse momentum differential cross section for different pairs of $D$-mesons. The theoretical results consider the center-of-mass energy and forward rapidities associated to the measurements by the LHCb Collaboration. The results considering different unintegrated gluon distributions are presented and compared to data and predictions for proton-nucleus collisions are provided.

7.Normalized factorial moments of spatial distributions of particles in high multiplicity events: A Toy model study

Authors:Sheetal Sharma, Salman Khurshid Malik, Zarina Banoo, Ramni Gupta

Abstract: Scaling behavior of normalized factorial moments ($F_{q}$) of spatial distributions of the particles comprising a system may be studied to probe and to determine its characteristics. In heavy-ion collisions at ultra-relativistic energies, a strongly interacting complex system of quarks and gluons is created. The nature of the system created and multi particle production mechanism in these collisions is predicted to be revealed by the study of normalized factorial moments ($F_{{\rm{q}}}$) as function of various parameters. In this work, observations from the Toy model study of the scaling behavior of $F_{{\rm{q}}}$ moments, resilience of these moments to detector efficiencies and sensitivity towards fluctuations in the system will be presented.

8.Predictions of the Strange partner of $T_{cc}$ in the quark delocalization color screening model

Authors:Xuejie Liu, Dianyong Chen, Hongxia Huang, Jialun Ping

Abstract: Inspired by the detection of $T_{cc}$ tetraquark state by LHCb Collaboration, we preform a systemical investigation of the low-lying doubly heavy charm tetraquark states with strangeness in the quark delocalization color screening model in the present work. Two kinds of configurations, the meson-meson configuration and diquark-antidiquark configuration, are considered in the calculation. Our estimations indicate that the coupled channel effects play important role in the multiquark system, and a bound state with $J^{P}=1^{+}$ and a resonance state with $J^{P}=0^{+}$ have been predicted. The mass of the bound state is evaluated to be $(3971\sim3975)$ MeV, while the mass and width of the resonance are determined to be $(4113\sim4114)$ MeV and $(14.3\sim 16.1)$ MeV, respectively.

9.An Unfamiliar Way to Generate the Hierarchy of Standard Model Fermion Masses

Authors:S. Baek, J. Kersten, P. Ko, L. Velasco-Sevilla

Abstract: While the properties of the observed Higgs boson agree with the Standard Model predictions, the hierarchy of fermion masses lacks an explanation within the model. In this work, we propose a fresh approach to this problem, involving a different Higgs doublet responsible for each quark mass. We construct a model with a gauged, non-anomalous $U(1)$ family symmetry that fixes which fermion couples to which doublet with an $\mathcal{O}(1)$ Yukawa coupling. The hierarchy of masses is generated by the hierarchy of vacuum expectation values of the Higgs fields. The model generically predicts a light, weakly coupled pseudoscalar. We verify that the model satisfies constraints from flavour changing neutral currents, Higgs phenomenology and electroweak precision tests.

10.Additional Higgs Bosons near 95 and 650 GeV in the NMSSM

Authors:Ulrich Ellwanger, Cyril Hugonie

Abstract: Hints for an additional Higgs boson with a mass of about 95 GeV originate from LEP and searches in the diphoton channel by CMS and ATLAS. A search for resonant production of SM plus BSM Higgs bosons in the diphoton plus bb channel by CMS showed some excess for a 650 GeV resonance decaying into the SM Higgs plus a 95 GeV Higgs boson. We investigate whether these phenomena can be interpreted simultaneously within the NMSSM subject to the latest constraints on couplings of the SM Higgs boson, on extra Higgs bosons from the LHC, and on dark matter direct detection cross sections.

11.Interplay between Higgs inflation and dark matter models with dark $U(1)$ gauge symmetry

Authors:Sarif Khan, Jinsu Kim, Pyungwon Ko

Abstract: We investigate dark matter phenomenology and Higgs inflation in a dark $U(1)_D$-extended model. The model features two dark matter candidates, a dark fermion and a dark vector boson. When the fermion DM $\psi$ is heavier than the vector DM $W_D$, there is an ample parameter space where $\psi$ is dominant over $W_D$. The model can then easily evade the stringent bounds from direct detection experiments, since $\psi$ has no direct coupling to the Standard Model particles. Furthermore, the model can accommodate inflation in three different ways, one along the Standard Model Higgs direction, one along the dark Higgs direction, and one along the combination of the two. Considering the running of the parameters and various observational constraints, we perform a detailed numerical analysis and identify allowed parameter spaces that explain both dark matter and Higgs inflation in a unified manner. We discuss in detail how the imposition of Higgs inflation severely constrains the dark matter parameter space. The existence of the dark Higgs field is found to play a crucial role both in dark matter phenomenology and in generalised Higgs inflation.

12.Recent Progress in Low Energy Neutrino Scattering Physics and Its Implications for the Standard and Beyond the Standard Model Physics

Authors:V. Pandey

Abstract: Neutrinos continue to provide a testing ground for the structure of the standard model of particle physics as well as hints towards the physics beyond the standard model. Neutrinos of energies spanning over several orders of magnitude, originating in many terrestrial and astrophysical processes, have been detected via various decay and interaction mechanisms. At MeV scales, there has been one elusive process, until a few years ago, known as coherent elastic neutrino-nucleus scattering (CEvNS) that was theoretically predicted over five decades ago but was never observed experimentally. The recent experimental observation of the CEvNS process by the COHERENT collaboration at a stopped pion neutrino source has inspired physicists across many subfields. This has vital implications for nuclear physics, high-energy physics, astrophysics, and beyond. CEvNS, being a low-energy process, provides a natural window to study light, weakly-coupled, new physics in the neutrino sector. In this review, we intend to provide the current status of low energy neutrino scattering physics and its implications for the standard and beyond the standard model physics. We discuss the general formalism of calculating the tree-level CEvNS cross section and present estimated theoretical uncertainties on the CEvNS cross section stemming from different sources. We also discuss the inelastic scattering of tens of MeV neutrinos that have implications for supernova detection in future neutrino experiments. We discuss how the CEvNS experiments can be used as a testing ground for the Standard Model (SM) weak physics as well as in searching for the Beyond the Standard Model (BSM) physics signals. Any deviation from the SM predicted event rate either with a change in the total event rate or with a change in the shape of the recoil spectrum, could indicate new contributions to the interaction cross-section.

13.Conformal Little Higgs

Authors:Aqeel Ahmed, Manfred Lindner, Philipp Saake

Abstract: Little Higgs models address the hierarchy problem by identifying the SM Higgs doublet as pseudo-Nambu--Goldstone bosons (pNGB) arising from global symmetries with collective breakings. These models are designed to address the little hierarchy problem up to a scale of $\Lambda\!\sim\! {\cal O}(10)~$TeV. Consequently, these models necessitate an ultraviolet (UV) completion above this scale. On the other hand, conformal extensions of the Standard Model are intriguing because scales emerge as a consequence of dimensional transmutation. In this study, we present a unified framework in which the electroweak hierarchy problem is tackled through a conformal symmetry collectively broken around the TeV scale, offering an appealing UV completion for Little Higgs models. Notably, this framework automatically ensures the presence of the required UV fixed points, eliminating the need for careful adjustments to the particle content of the theory. Moreover, this framework naturally addresses the flavor puzzles associated with composite or Little Higgs models. Furthermore, we suggest that in this framework all known Little Higgs models can be UV-completed through conformal dynamics above the scale $\Lambda$ up to arbitrary high scales.

14.Method for measuring the proton charge radius from the time-like region

Authors:Yong-Hui Lin, Feng-Kun Guo, Ulf-G. Meißner

Abstract: We propose a novel method for measuring the proton charge radius. The method explores the facts that the Dalitz decay $J/\psi \to p\bar{p}e^+e^-$ contains the proton form factors and the measurable lowest four-momentum transfer squared value can be as low as $\sim 4m_e^2= 1.05\times10^{-6}$ GeV$^2$ in the time-like region. We identify a kinematic region where the proton form factors are essential and propose a method for subtracting the background from the data. It is estimated that the proton charge radius can be measured to a precision of 0.04 fm at the BESIII setup and one order of magnitude better at the future Super $\tau$-Charm Facility. Furthermore, the same method can be used to measure the charge radii of charged hyperons, which are otherwise difficult to access.

15.Identifying the Group-Theoretic Structure of Machine-Learned Symmetries

Authors:Roy T. Forestano, Konstantin T. Matchev, Katia Matcheva, Alexander Roman, Eyup B. Unlu, Sarunas Verner

Abstract: Deep learning was recently successfully used in deriving symmetry transformations that preserve important physics quantities. Being completely agnostic, these techniques postpone the identification of the discovered symmetries to a later stage. In this letter we propose methods for examining and identifying the group-theoretic structure of such machine-learned symmetries. We design loss functions which probe the subalgebra structure either during the deep learning stage of symmetry discovery or in a subsequent post-processing stage. We illustrate the new methods with examples from the U(n) Lie group family, obtaining the respective subalgebra decompositions. As an application to particle physics, we demonstrate the identification of the residual symmetries after the spontaneous breaking of non-Abelian gauge symmetries like SU(3) and SU(5) which are commonly used in model building.

16.Single-soft emissions for amplitudes with two colored particles at three loops

Authors:Franz Herzog, Yao Ma, Bernhard Mistlberger, Adi Suresh

Abstract: We compute the three-loop correction to the universal single-soft emission current for the case of scattering amplitudes with two additional color-charged partons. We present results valid for QCD and $\mathcal{N}=4$ super-symmetric Yang-Mills theory. To achieve our results we develop a new integrand expansion technique for scattering amplitudes in the presence of soft emissions. Furthermore, we obtain contributions from single final-state parton matrix elements to the Higgs boson and Drell-Yan production cross section at next-to-next-to-next-to-next-to leading order (N$^4$LO) in perturbative QCD in the threshold limit.

17.Exploring the covariant form factors for spin-1 particles

Authors:J. P. B. C. de Melo Laboratório de Física Teórica e Computacional - LFTC, Universidade Cruzeiro do Sul and Universidade Cidade de São Paulo

Abstract: The spin-1 particles is an admirable two quarks bound state system to understand electromagnetic properties from hadronic states. These systems are generally relativistic, and therefore, need an approach using quantum field theory. In the present work, we will use both the quantum field theory at the instant form, as well, quantum field theory on the light-front~(LFQFT). In general, it is used to calculate the electromagnetic properties of spin-1 vector particles in the LFQFT formalism, with the plus component of the electromagnetic current. In the present work, we used, in addition to the plus component of the electromagnetic current; the minus component of the current, and we use that components o the current, to extract the covariant form factors; showing that to have an equivalence between these we need to add non-valence terms to the electromagnetic current, in order to restore the covariance, and obtain exactly the same results when using the instant form quantum field theory.

18.Pseudoscalar current and covariance with the light-front approach

Authors:Jurandi Leãoo Laboratório de Física Teórica e Computacional-LFTC, Universidade Cruzeiro do Sul / Universidade Cidade de São Paulo, and Instituto Federal de São Paulo, Avenida Bahia, Caraguatatuba, 11665-071 São Paulo, Brazil, J. P. B. C. de Melo Laboratório de Física Teórica e Computacional-LFTC, Universidade Cruzeiro do Sul / Universidade Cidade de São Paulo, 015060-000, São Paulo, SP, Brazil

Abstract: Quantum Field Theory (QFT) is used to describe the physics of particles in terms of their fundamental constituents. The Light-Front Field Theory~(LFFT), introduced by Paul Dirac in 1949, is an alternative approach to solve some of the problems that arise in quantum field theory. The LFFT is similar to the Equal Time Quantum Field Theory~(EQT), however, some particularities are not, such as the loss of covariance in the light-front. Pion electromagnetic form factor is studied in this work at lower and higher momentum transfer regions to explore the constituent quark models and the differences among these and other models. The electromagnetic current is calculated with both the ``plus'' and ``minus'' components in the light-front approach. The results are compared with other models, as well as with experimental data.

19.Dark Matter Direct Detection in $t$-channel mediator models

Authors:Giorgio Arcadi, David Cabo-Almeida, Federico Mescia, Javier Virto

Abstract: We provide a complete reappraisal for the Direct Detection phenomenology of Dark Matter $t$-channel portal models. We provide a complete computation of the loop induced direct detection cross-section for both scalar and fermionic Dark Matter candidates. The results are compared with current and future bounds from direct detection experiments as well as with the requirement of the correct Dark Matter relic density.

1.QCD phase transitions in the light quark chiral limit

Authors:Julian Bernhardt, Christian S. Fischer

Abstract: We investigate the order of the QCD chiral transition in the limit of vanishing bare up/down quark masses and variations of the bare strange quark mass $0 \le m_{\mathrm{s}} \le \infty$. In this limit and due to universality long range correlations with the quantum numbers of pseudoscalar and scalar mesons may dominate the physics. In order to study the interplay between the microscopic quark and gluon degrees of freedom and the long range correlations we extend a combination of lattice Yang--Mills theory and a (truncated) version of Dyson--Schwinger equations by also taking back-reactions of mesonic degrees of freedom into account. Both this system and the meson backcoupling approach have been studied extensively in the past but this is the first work in a full $(2 + 1)$-flavor setup. Starting from the physical point, we determine the chiral susceptibilities for decreasing up/down quark masses and find good agreement with both lattice and functional renormalization group results. We then proceed to determine the order of the chiral transition along the left hand side of the Columbia plot, for chemical potentials in the range $-(30 \,\textrm{MeV})^2 \le \mu_q^2 \le (30 \,\textrm{MeV})^2$. We find a second-order phase transition throughout and no trace of a first-order region in the $N_{f} = 3$ corner of the Columbia plot. This result remains unchanged when an additional Goldstone boson due to a restored axial $\mathrm{U_A}(1)$ is taken into account.

2.Novel relations for twist-3 tensor-polarized fragmentation functions in spin-1 hadrons

Authors:Qin-Tao Song

Abstract: There are three types of fragmentation functions (FFs) which are used to describe the twist-3 cross sections of the hard semi-inclusive processes under QCD collinear factorization, and they are called intrinsic, kinematical, and dynamical FFs. In this work, we investigate the theoretical relations among these FFs for a tensor-polarized spin-1 hadron. Three Lorentz-invariance relations (LIRs) are derived by using the identities between the nonlocal quark-quark and quark-gluon-quark operators, which guarantee the frame independence of the twist-3 spin observables. The QCD equation of motion (e.o.m.) relations are also presented for the tensor-polarized FFs. In addition, we also show that the intrinsic and kinematical twist-3 FFs can be decomposed into the contributions of twist-2 FFs and twist-3 three-parton FFs, and the latter are also called dynamical FFs. If one neglects the dynamical FFs, we can obtain relations which are analogous to the Wandzura-Wilczek (WW) relation. Then, the intrinsic and kinematical twist-3 FFs are expressed in terms of the leading-twist ones. Since the FFs of a spin-1 hadron can be measured at various experimental facilities in the near future, these theoretical relations will play an important role in the analysis of the collinear tensor-polarized FFs.

3.Investigating Boson Sector in an Extended Standard Model with $U(1)_D$ Symmetry

Authors:Apriadi Salim Adam, Yunita Kristanti Andriani, Eny Latifah

Abstract: We have investigated the boson sector in an extended standard model (SM) with additional $U(1)_D$ symmetry. In the proposed model, the singlet scalar and doublet scalar Higgs are added in addition to the SM-like scalar Higgs. These scalars are also coupled to the gauge boson fields. In this work, we calculate the masses of both gauge and scalar Higgs bosons. Their masses are obtained through spontaneous symmetry breaking using the Higgs fields with non-zero vacuum expectation values. We also study numerically the positivity conditions of the vacuum expectation value of the scalars. In particular, we perform scanning of the parameter space of the potential and study the obtained scalar mass dependence on the parameter of the model.

4.Listening for the Axion Echo with the 21 CentiMeter Array

Authors:Ariel Arza, Quan Guo, Lei Wu, Qiaoli Yang, Xiaolong Yang, Qiang Yuan, Bin Zhu

Abstract: The axion is a hypothetical elementary particle that could solve the long-standing strong CP problem in particle physics and the dark matter mystery in the cosmos. Due to the stimulation of the ambient photons, the axion dark matter decay into photons is significantly enhanced so that its echo signal could be detected by terrestrial telescopes. As a pathfinder, we study the expected sensitivity of searching for the axion dark matter in the mass range between $0.41$ and $1.6\mu\text{eV}$ with the 21 CentiMeter Array (21CMA). We aim to cover the whole 21CMA frequency range in two years by using a 1MW emitter. We find that the resulting sensitivity on the axion-photon coupling could surpass other existing limits by about one order of magnitude.

5.Analytic Solution to Neutrino Oscillation in Constant Matter Density, and Fast Algorithm

Authors:James Page

Abstract: A recently published method for solving the neutrino evolution equation with constant matter density is further refined and used to lay out a fast and accurate algorithm for computing transition and survival probabilities. In particular, the three examples of $\overline{\nu}_e$ survival, $\overline{\nu}_\mu$ survival and $\overline{\nu}_e$ appearance probabilities are written in terms of mixing angles, mass differences and matter electron density. A program based on this new method is found to be roughly twice as fast as, and in agreement with, the leading GLoBES package. Furthermore, the behaviour of all relevant effective parameters is sketched out in terms of a range of neutrino energies, or matter electron densities. For instance, the $\overline{\nu}_e$ survival probability in constant matter density is found to have no dependence on the mixing angle $\theta_{23}$ or the CP-violating phase $\delta_{13}$.

6.Anomaly-free dark matter models with one-loop neutrino masses and a gauged U(1) symmetry

Authors:T. de Boer, M. Klasen, S. Zeinstra

Abstract: We systematically study and classify scotogenic models with a local U(1) gauge symmetry. These models give rise to radiative neutrino masses and a stable dark matter candidate, but avoid the theoretical problems of global and discrete symmetries. We restrict the dark sector particle content to up to four scalar or fermionic SU(2) singlets, doublets or triplets and use theoretical arguments based on anomaly freedom, Lorentz and gauge symmetry to find all possible charge assignments of these particles. The U(1) symmetry can be broken by a new Higgs boson to a residual discrete symmetry, that still stabilizes the dark matter candidate. We list the particle content and charge assignments of all non-equivalent models. Specific examples in our class of models that have been studied previously in the literature are the U(1)$_D$ scotogenic and singlet-triplet scalar models breaking to $Z_2$. We also briefly discuss the new phenomenological aspects of our model arising from the presence of a new massless dark photon or massive $Z'$ boson as well as the additional Higgs boson.

7.New Inflation in Waterfall Region

Authors:Niamat Ullah Khan, Nadir Ijaz, Mansoor Ur Rehman

Abstract: We introduce a class of new inflation models within the waterfall region of a generalized hybrid inflation framework. The initial conditions are generated in the valley of hybrid preinflation. Both single-field and multi-field inflationary scenarios have been identified within this context. A supersymmetric realization of this scenario can successfully be achieved within the tribrid inflation framework. To assess the model's viability, we calculate the predictions of inflationary observables using the $\delta N$ formalism, demonstrating excellent agreement with the most recent Planck data. Furthermore, this model facilitates successful reheating and nonthermal leptogenesis, with the matter-field component of the inflaton identified as a sneutrino.

8.Dynamics of Superconformal Axion: Quality and Scalegenesis

Authors:Shota Nakagawa, Yuichiro Nakai, Masaki Yamada, Yufei Zhang

Abstract: We explore a dynamical mechanism to realize the emergence of a global $U(1)_{\rm PQ}$ symmetry and its spontaneous breaking at an intermediate scale for an axion solution to the strong CP problem. Such a dynamics is provided by a new supersymmetric QCD near the middle of conformal window that couples to fields spontaneously breaking the $U(1)_{\rm PQ}$ symmetry. A large anomalous dimension of the $U(1)_{\rm PQ}$ breaking fields leads to the suppression of explicit $U(1)_{\rm PQ}$-violating higher dimensional operators. The $U(1)_{\rm PQ}$ breaking vacuum is generated at a scale hierarchically smaller than the Planck scale by a non-perturbative effect. The $U(1)_{\rm PQ}$ breaking drives the conformal breaking, and all the new quarks become massive. The axion potential is generated by the ordinary color $SU(3)_C$ effect as the $U(1)_{\rm PQ}$ symmetry is only anomalous under the $SU(3)_C$. The saxion direction is stabilized by supersymmetry breaking and cosmologically harmless.

9.Low-energy flavour probes of light vector bosons

Authors:Luca Di Luzio, Gabriele Levati, Paride Paradisi, Xavier Ponce Díaz

Abstract: In this work, we construct the chiral Lagrangian for a light spin-1 boson $X$ possessing both vectorial and axial couplings to the light Standard Model quarks $u, d, s$. We then use it in order to describe the tree-level, model-independent contributions to the $\Delta S = 1$ transition $K^\pm \rightarrow \pi^\pm X$, which is induced by Standard Model charged currents and is possibly enhanced by the emission of a longitudinally polarized $X$ boson. Such a flavour observable is then shown to set the best model-independent bounds on the diagonal axial couplings of $X$ to light quarks in the mass range allowed by the decay kinematics, improving the currently available constraints from beam-dump experiments and collider searches.

10.Collective excitations of a hot QCD medium in a time dependent background magnetic field

Authors:Gowthama K K, Vinod Chandra

Abstract: Collective modes within a hot Quantum Chromodynamics (QCD) medium are obtained from the polarization tensor, considering both constant and time-varying electromagnetic fields. In both scenarios, five complex modes emerge, reliant on the wave vector ($k$), with electrical conductivity exerting significant influence. The impact of the modes on the energy loss of heavy quarks in the hot QCD medium with a background electromagnetic field has been studied by obtaining the induced electric field in terms of the polarization tensor while invoking Wong's equations. The findings are seen to be consistent with analogous approaches, reinforcing the significance of the results.

1.The Curious Early History of CKM Matrix -- miracles happen!

Authors:Stephen Lars Olsen

Abstract: The 1973 Kobayashi Maskawa paper proposed a compelling link between Cabibbo's flavor-mixing scheme and CP violation but, since it required the existence of six quarks at a time when the physics community was happy with only three, it received zero attention. However, two years after the paper appeared -- at which time it had received a grand total of two citations -- the charmed quark was discovered and it finally got some notice and acceptance. After this stumbling start, it subsequently emerged as the focal point of an enormous amount of experimental and theoretical research activity. In an invited talk at a KEK symposium to celebrate the 50th anniversary of the KM paper, I reviewed some of the less well known circumstances that occurred in the years preceding and following the paper's appearance.

2.QED at NNLO and beyond for precision experiments

Authors:Yannick Ulrich

Abstract: Low-energy experiments allow for some of the most precise measurements in particle physics, such as $g-2$. To make the most of these experiments, theory needs to match the experimental precision. Over the last decade, this meant that even in QED next-to-next-to-leading order calculations (or even more in some cases) became necessary. McMule (Monte Carlo for MUons and other LEptons) is a framework that we have developed to obtain NNLO predictions for a number of processes, such as $e\mu \to e\mu$, $ee\to ee$, and $\mu\to e\nu\bar\nu$. I will discuss some of the challenges faced when dealing with QED corrections and some possible solutions we have implemented in McMule, namely the subtraction scheme FKS$^\ell$, massification, and next-to-soft stabilisation. I will also demonstrate how to calculate the three-loop massification constant that will be required at N$^3$LO.

3.Muon-electron scattering at NNLO with McMule

Authors:Marco Rocco

Abstract: A recently proposed experiment, MUonE, aims to extract the hadronic vacuum polarisation contribution to the muon g-2 from muon-electron scattering at low energy. The extrapolation requires that both experimental and theoretical uncertainties do not exceed 10 ppm. This corresponds, at least, to next-to-next-to-leading-order (NNLO) QED corrections to $e \mu \to e \mu$. I will discuss the implementation of a Monte Carlo integrator for this process in the McMule framework arXiv:2212.06481, which provides infrared-safe differential results at said order in QED. An approximation of the MUonE setup provides some phenomenological results and sheds light on the need for beyond-NNLO corrections, which are currently under study within McMule.

4.Direct bounds on Left-Right gauge boson masses at LHC Run 2

Authors:Sergio Ferrando Solera, Antonio Pich, Luiz Vale Silva

Abstract: While the third run of the Large Hadron Collider (LHC) is ongoing, the underlying theory that extends the Standard Model remains so far unknown. Left-Right Models (LRMs) introduce a new gauge sector, and can restore parity symmetry at high enough energies. If LRMs are indeed realized in nature, the mediators of the new weak force can be searched for in colliders via their direct production. We recast existing experimental bounds from LHC Run 2 on the heavy LRM gauge boson masses. As a novelty, we discuss the effect of the LRM scalar content on the total width of the new gauge bosons, obtaining model-independent bounds within the specific realizations of the LRM scalar sectors analysed here. These bounds avoid the need to detail the spectrum of the scalar sector, and apply in the general case where no discrete symmetry is enforced. Moreover, we emphasize the effect of the structure of the quark right-handed mixing matrix on the charged LRM gauge boson production at LHC. We find that $W_R$ and $Z_R$ masses are constrained to lie above $2$ TeV and $4$ TeV, respectively.

5.Split gluon masses in $SU(N)\times SU(M)$ theories

Authors:Julia Gómez Concejo, Felipe J. Llanes-Estrada, Diego María-Almazán, Alexandre Salas-Bernárdez

Abstract: We extend a known mass-gap equation for pure gluodynamics in global colour models (formulated in equal time quantization in Coulomb gauge) to one in which gluons split into two sets which may have different masses. If the theory is $SU(N)\times SU(M)$ with gluons in both groups having identical couplings (as suggested by Grand Unification arguments at large scales) it is immediate to see that different masses are generated for each subgroup. This global symmetry is not broken, but the split masses erase accidental symmetries that might be present due to the two couplings being the same at the large scale, such as $SU(N\times M)$ or similar. We also numerically explore a couple of low-dimensional examples of simple Lie groups, but in spite of the system having a form that would seem to allow spontaneous symmetry breaking, it is not triggered for these groups whose algebra has no ideal, and the dispersion relations for the various gluons converge to the same form.

6.Exploring Anisotropic flow via the Boltzmann Transport Equation Employing the Tsallis Blast Wave Description at LHC energies

Authors:Aviral Akhil, Swatantra Kumar Tiwari

Abstract: Anisotropic flow $i.e.$ azimuthal anisotropies in particle production are one of the important probes in characterizing the properties of the strongly interacting matter created in the relativistic heavy-ion collisions. These observables are sensitive to both the transport properties as well as the equation of state (EOS) of Quantum Chromodynamics (QCD) matter. We have adopted the Boltzmann transport equation (BTE) in the relaxation time approximation (RTA) to describe the experimental data for harmonic flows such as elliptic flow ($v_2$), triangular flow ($v_3$), quadrangular flow ($v_4$) obtained in heavy-ion collisions at Large Hadron Collider (LHC) energies. In this analysis, we have used Tsallis statistics as an initial distribution and the Tsallis Blast wave (TBW) description is used as the equilibrium distribution function while describing the evolution of the particle production in BTE. We have fitted the transverse momentum spectra, $v_2$, $v_3$, and $v_4$ of identified hadrons such as pion, kaon, and proton for Pb-Pb and Xe-Xe collisions at the LHC energies of $\sqrt{s_{NN}}$ = 5.02 TeV and $\sqrt{s_{NN}}$ = 5.44 TeV, respectively for various centralities. Our study offers a comparative analysis between the two distinct collision systems operating at comparable collision energies. The present formulation successfully fits the experimental data for $p_T$-spectra upto $p_T$ = 8 GeV and effectively explains the anisotropic flows data upto $p_T$ = 10 GeV with a very favourable $\chi^2/ndf$. We observe that the average transverse flow velocity ($<\beta_r>$) and the kinetic freeze-out temperature ($T$) extracted in our analysis decrease as we go towards the peripheral collisions. The azimuthal modulation amplitudes ($\rho_a$) exhibit an increasing pattern as one moves from central to peripheral collisions in both the Pb-Pb and Xe-Xe nuclei interactions.

7.A consistent resummation of mass and soft logarithms in processes with heavy flavours

Authors:Andrea Ghira, Simone Marzani, Giovanni Ridolfi

Abstract: Perturbative calculations for processes that involve heavy flavours can be performed in two approaches: the massive scheme and the massless one. The former enables one to fully account for the heavy-quark kinematics, while the latter allows one to resum potentially-large mass logarithms. Furthermore, the two schemes can be combined to take advantage of the virtues of each of them. Both massive and massless calculations can be supplemented by soft-gluon resummation. However matching between massive and massless resummed calculations is difficult, essentially because of the non-commutativity of the soft and massless limits. In this paper, we develop a formalism to combine resummed massive and massive calculations. We obtain an all-order expression that consistently resums both mass and soft logarithms to next-to-leading logarithmic accuracy. We perform detailed calculations for the decay of the Higgs into a heavy-quark pair and discuss the applications of this formalism to different processes.

8.$D_{(s)}-$ mesons semileptonic form factors in the 4-flavor holographic QCD

Authors:Hiwa A. Ahmed, Yidian Chen, Mei Huang

Abstract: We investigate semileptonic form factors of $D_{(s)}$ meson from a modified soft-wall 4-flavor holographic model. The model successfully reproduces the masses and decay constants of various mesons, including $\rho$, $K^*$, $D^*$, $D_s^*$, $a_1$, $K_1$, $f_1$, $D_1$,$D_{s1}$, $\pi$, $K$, $\eta$, $D$, and $D_s$. Moreover, we study the semileptonic decay processes $D^{+} \to (\pi, K, \eta) l^{+} \nu_{l}$ and $D_{s}^{+} \to ( K, \eta) l^{+} \nu_{l}$, associated with the vector meson exchange, as well as $D_{(s)}^{+} \to K^{} l^{+} \nu_{l}$, associated with the vector and axial vector meson exchange. The form factors $f_{+}(q^{2})$ for $D \to\pi$ and $D_{(s)}\to K$ decays agree excellently with experimental and lattice data, outperforming other theoretical approaches. The $f_{+}(q^{2})$ form factor for $D^{+} \to \eta $ is compatible with experimental data, while a slight discrepancy is observed for $D_{s}^{+} \to \eta $ at large $q^{2}$. Additionally, we predict the vector form factors $V(q^{2})$ and $A_{1}(q^{2})$ for $D \to K^{}$ and $D_{s} \to K^{}$ decays, respectively. The results agree well with other approaches and lattice data at maximum recoil ($q^{2}=0$).

9.Quantum algorithms for the simulation of perturbative QCD processes

Authors:Herschel A. Chawdhry, Mathieu Pellen

Abstract: Quantum computers are expected to give major speed-ups for the simulation of quantum systems. In these conference proceedings, we discuss quantum algorithms for the simulation of perturbative Quantum Chromodynamics (QCD) processes. In particular, we describe quantum circuits for simulating the colour part of the interactions of quarks and gluons. We implement our circuits on a simulated noiseless quantum computer and validate them by calculating colour factors for various examples of Feynman diagrams.

10.Assumption Breakdown in Radiative Energy Loss

Authors:Coleridge Faraday, W. A. Horowitz

Abstract: We show that an integral assumption in DGLV radiative energy loss - the large formation time assumption - is violated at high-$p_T$ for phenomenologically relevant parameters. We further investigate the phenomenological impact of placing a new kinematic bound on the radiated gluon transverse momentum, which ensures that there are no contributions to the energy loss from regions of parameter space that violate the large formation time assumption. We find that this places a large sensitivity on the exact kinematic cutoff used, similar to the known collinear cutoff sensitivity, indicating the theoretical need for a rederivation of DGLV radiative energy with the large formation time assumption relaxed in order to make rigorous predictions. We additionally find that this large formation time cutoff dramatically reduces the size of a short pathlength correction to the DGLV radiative energy loss, which is of phenomenological interest in predicting suppression in small $p +A$ systems. We compute the phenomenological predictions utilizing this large formation time cutoff in both $p+A$ and $A+A$ collisions at the LHC, in a convolved radiative and elastic energy loss model.

11.Scale dependence of non-factorizable virtual corrections to Higgs boson production in weak boson fusion

Authors:Christian Brønnum-Hansen, Ming-Ming Long, Kirill Melnikov

Abstract: The renormalization-scale dependence of the non-factorizable virtual corrections to Higgs boson production in weak boson fusion at next-to-next-to-leading order in perturbative QCD is unusually strong, due to the peculiar nature of these corrections. To address this problem, we compute the three-loop non-factorizable contribution to this process which accounts for the running of the strong coupling constant, and show that it stabilizes the theoretical prediction.

12.The Interplay Between the Muon $g-2$ Anomaly and the PTA nHZ Gravitational Waves from Domain Walls in NMSSM

Authors:Ming Xia Huang, Fei Wang, Ying Kai Zhang

Abstract: Domain walls (DWs) from spontaneously breaking of the discrete symmetry in approximate $Z_3$-invariant NMSSM can collapse and lead to the stochastic gravitational waves (GWs) background signals observed by PTA collaborations with the presence of some explicitly $Z_3$ breaking terms in the NMSSM effective superpotential and scalar potential. In the presence of a hidden sector, such terms may origin from the geometric superconformal breaking with holomorphic quadratic correction to frame function when the global scale-invariant superpotential is naturally embedded into the canonical superconformal supergravity models. The smallness of such mass parameters in the NMSSM may be traced back to the original superconformal invariance. Naive estimations indicate that SUSY explanation to muon $g-2$ anomaly can have tension with the constraints on SUSY by PTA data, because large SUSY contributions to $\Delta a_\mu$ in general needs relatively light superpartners while present $\Omega_{gw}^0$ can set the lower bounds for $m_{soft}$. We calculate numerically the signatures of GWs produced from the collapse of DWs and find that the observed nHZ stochastic GWs background by NANOGrav etc can indeed be explained with proper tiny values of $\chi m_{3/2}\sim 10^{-14}{\rm eV}$ for $\chi S^2$ case (and $\chi m_{3/2}\sim 10^{-10}{\rm eV}$ for $\chi H_u H_d$ case), respectively. Besides, there are still some parameter points, whose GWs spectra intersect with the NANOGrav signal region, can explain the muon $g-2$ anomaly to $1\sigma$ range.

13.Bose-Einstein condensation and muon production in ultra-high energy cosmic ray particle collisions

Authors:V. A. Okorokov National Research Nuclear University MEPhI

Abstract: Collisions of cosmic ray particles with ultra-high initial energies with nuclei in the atmosphere open a wide room for appearing of the novel dynamical features for multiparticle production processes. In particular, the pion-lasing behavior driven by Bose-Einstein condensation would result in the shift to larger multiplicities and, as consequence, could provide, in general, the enhanced yield of cosmic muons. In the present work the critical value of the space charged particle density for onset of Bose-Einstein condensation of the boson (pion) wave-packets into the same wave-packet state is estimated within the model with complete multiparticle symmetrization for the energy domain corresponded to the ultra-high energy cosmic rays (UHECR). Energy dependence of mean density of charged pions is evaluated for the cases of absent of the Bose-Einstein effects and for presence of laser-like behavior of pions. The possible influence of the Bose-Einstein condensation is discussed for the muon production in UHECR particle collisions with the atmosphere.

1.The cosmological collider signal in the non-BD initial states

Authors:Yuan Yin

Abstract: We investigate the cosmological collider (CC) signal arising from the tree-level exchange of a scalar spectator particle with a non-Bunch Davies (BD) initial state. We decompose the inflaton correlators into seed integrals, which we compute analytically by solving the bootstrap equations. We show that the non-BD initial state eliminates the Hubble scale Boltzmann suppression $e^{-\pi m /H}$ that usually affects the CC signal. Consequently, in this scenario, the CC can probe an energy scale much higher than the inflationary Hubble scale $H$.

2.Shear viscosity of rotating, hot, and dense spin-half fermionic systems from quantum field theory

Authors:Sarthak Satapathy, Rajeev Singh, Pushpa Panday, Salman Ahamad Khan, Debarshi Dey

Abstract: In this study, we calculate the shear viscosity for rotating fermions with spin-half under conditions of high temperature and density. We employ the Kubo formalism, rooted in finite-temperature quantum field theory, to compute the field correlation functions essential for this evaluation. The one-loop diagram pertinent to shear viscosity is analyzed within the context of curved space, utilizing tetrad formalism as an effective approach in cylindrical coordinates. Our findings focus on extremely high angular velocities, ranging from 0.1 to 1 GeV, which align with experimental expectations. Furthermore, we explore the interrelationship between the chemical potential and angular velocity within the scope of this study.

3.QCD parameters and SM-high precisions from $e^+e^-\to$ Hadrons : Summary

Authors:Stephan Narison LUPM-CNRS/IN2P3, Univ. Montpellier-FR and iHEPMAD, Univ. Antananarivo-MG

Abstract: In this talk, I summarize the results obtained recently in Ref.\,\cite{SNe} using the PDG 22 compilation of the $e^+e^-\to$ Hadrons $\oplus$ the recent CMD3 data for the pion form factor. Using the gluon condensate $\langle \alpha_s G^2\rangle=(6.49\pm 0.35)\times 10^{-2}$ GeV$^4$ from heavy quark sum rules, the extracted QCD four-quark and dimension eight condensate condensates values are: $\rho\alpha_s\langle\bar\psi\psi\rangle^2= (5.98\pm 0.64)\times 10^{-4}$ GeV$^6$ and $d_8= (4.3\pm 3.0)\times 10^{-2}$ GeV$^8$ from the ratio ${\cal R}_{10}$ of Laplace sum rules to order $\alpha_s^4$. Inversely using these estimated values of the condensates, we obtain from ${\cal R}_{10}$: $\langle \alpha_s G^2\rangle=(6.12\pm 0.61)\times 10^{-2}$ GeV$^4$ which leads to the average $(6.40\pm 0.30)\times 10^{-2}$ GeV$^4$. %from light and heavy quark systems. Using the lowest $\tau$-like decay moment, the mean result of Fixed Order (FO) and Contour Improved (CI) PT series within the standard OPE is : $\alpha_s(M_\tau)=0.3385(50)(136)_{syst}$ [resp. $0.3262(37)(78)_{syst}$] to order $\alpha_s^4$ [resp. $\alpha_s^5$] leading to $\alpha_s(M_Z)$=0.1207(17)(3) [resp. 0.1193(11)(3)], while the sum of the non-perturbative contribution at $M_\tau$ is\,: $\delta^V_{NP}(M_\tau)=(2.3\pm 0.2)\times 10^{-2}$. Using the same data, one also obtains the LO hadronic vacuum polarization to the muon and $\tau$ anomalous magnetic moments: $a_\mu\vert^{hvp}_{l.o}= (7036.5\pm 38.9)\times10^{-11}, \, a_\tau\vert^{hvp}_{l.o}= (3494.8\pm 24.7)\times10^{-9} $ which leads to : $\Delta a_\mu\equiv a_\mu^{exp}-a_\mu^{th} = (142\pm 42_{th}\pm 41_{exp})\times 10^{-11}$ and reduces the tension between the SM prediction and experiment. One also finds: $\alpha^{(5)}(M_Z)\vert_{had}=(2766.3\pm 4.5)\times 10^{-5}$.

4.Study of damped oscillating structures from charged and neutral K-meson electromagnetic form factors data

Authors:Stanislav Dubnička, Anna Zuzana Dubničková, Lukáš Holka, Andrej Liptaj

Abstract: The damped oscillating structures (OS) were recently revealed in the proton "effective" form factor (FF) data. For the time being they can be neither confirmed nor disproved by investigations of timelike data on the individual proton electric and proton magnetic FFs because their precision and reliability (especially of the proton electric FF data) has not achieved required level for this aim. On the other hand, conjectures that the OS are direct manifestations of the quark-gluon structure of the proton indicate that they must not be specific only for the proton and neutron, but that they should be present also for other hadrons. This opens a plausibility to find damped oscillatory structures also from the EM FFs data of such hadrons, for which adequate EM FFs data exist, by using the same procedure as for the proton. Consequently in this paper damped oscillatory structures are investigated in the EM FFs data of the charged and neutral $K$-mesons to be extracted from the corresponding production cross sections, $\sigma^{bare}_{tot}(e^+e^-\to K^+ K^-)$ measured from the threshold up to 64 GeV$^2$ and $\sigma^{bare}_{tot}(e^+e^-\to K_s K_L)$ measured from the threshold up to 9.5 GeV$^2$ of the total c.m. energy squared. The following results have been obtained. If the charged and neutral K-meson EM FFs timelike data are described by the three parametric formula by means of which OS have been revealed from the "effective" proton FF data then OS appear. If physically well founded Unitary and Analytic model of the K-meson EM structure is used for a description of the charged K-meson EM FFs data, no OS are visible. However, in the case of the neutral K-meson EM FF data one cannot make a definite decision. The overall results indicate that OS obtained from the "effective" proton FF data are likely an artefact of the three parametric formula which does not describe these data well.

5.LHC Study of Third-Generation Scalar Leptoquarks with Machine-Learned Likelihoods

Authors:Ernesto Arganda, Daniel A. Díaz, Andres D. Perez, Rosa M. Sandá Seoane, Alejandro Szynkman

Abstract: We study the impact of machine-learning algorithms on LHC searches for leptoquarks in final states with hadronically decaying tau leptons, multiple $b$-jets, and large missing transverse momentum. Pair production of scalar leptoquarks with decays only into third-generation leptons and quarks is assumed. Thanks to the use of supervised learning tools with unbinned methods to handle the high-dimensional final states, we consider simple selection cuts which would possibly translate into an improvement in the exclusion limits at the 95$\%$ confidence level for leptoquark masses with different values of their branching fraction into charged leptons. In particular, for intermediate branching fractions, we expect that the exclusion limits for leptoquark masses extend to $\sim$1.3 TeV. As a novelty in the implemented unbinned analysis, we include a simplified estimation of some systematic uncertainties with the aim of studying their possible impact on the stability of the results. Finally, we also present the projected sensitivity within this framework at 14 TeV for 300 and 3000 fb$^{-1}$ that extends the upper limits to $\sim$1.6 and $\sim$1.8 TeV, respectively.

6.The role of de-excitation in the final-state interactions of protons in neutrino-nucleus interactions

Authors:Anna Ershova, Kajetan Niewczas, Sara Bolognesi, Alain Letourneau, Jean-Christophe David, José Luís Rodríguez-Sánchez, Jan Sobczyk, Adrien Blanchet, Margherita Buizza Avanzini, Jaafar Chakrani, Joseph Cugnon, Stephen Dolan, Claudio Giganti, Samira Hassani, Jason Hirtz, Shivam Joshi, Cezary Juszczak, Laura Munteanu, Davide Sgalaberna, Uladzislava Yevarouskaya

Abstract: Present and next generation of long-baseline accelerator experiments are bringing the measurement of neutrino oscillations into the precision era with ever-increasing statistics. One of the most challenging aspects of achieving such measurements is developing relevant systematic uncertainties in the modeling of nuclear effects in neutrino-nucleus interactions. To address this problem, state-of-the-art detectors are being developed to extract detailed information about all particles produced in neutrino interactions. To fully profit from these experimental advancements, it is essential to have reliable models of propagation of the outgoing hadrons through nuclear matter able to predict how the energy is distributed between all the final-state observed particles. In this article, we investigate the role of nuclear de-excitation in neutrino-nucleus scattering using two Monte Carlo cascade models: NuWro and INCL coupled with the de-excitation code ABLA. The ablation model ABLA is used here for the first time to model de-excitation in neutrino interactions. As input to ABLA, we develop a consistent simulation of nuclear excitation energy tuned to electron-scattering data. The paper includes the characterization of the leading proton kinematics and of the nuclear cluster production during cascade and de-excitation. The observability of nuclear clusters as vertex activity and their role in a precise neutrino energy reconstruction is quantified.

7.B meson decays in covariant confined quark model

Authors:Stanislav Dubnička, Anna Zuzana Dubničková, Mikhail Alekseevich Ivanov, Andrej Liptaj

Abstract: The aim of this text to present the covariant confined quark model (CCQM) and review its applications to the decays of $B$ mesons. We do so in the context of existing experimental measurements and theoretical results of other authors, which we review also. The physics principles are in detail exposed for the CCQM, the other results (theoretical and experimental) are surveyed in an enumerative way with comments. We proceed by considering successively three categories of decay processes: leptonic, semileptonic and non-leptonic.

8.An improved method to determine the $Ξ_c-Ξ_c'$ mixing

Authors:Hang Liu, Wei Wang, Qi-An Zhang

Abstract: We develop an improved method to explore the $\Xi_c- \Xi_c'$ mixing which arises from the flavor SU(3) and heavy quark symmetry breaking. In this method, the flavor eigenstates under the SU(3) symmetry are at first constructed and the corresponding masses can be nonperturbatively determined. Matrix elements of the mass operators which break the flavor SU(3) symmetry sandwiched by the flavor eigenstates are then calculated. Diagonalizing the corresponding matrix of Hamiltonian gives the mass eigenstates of the full Hamiltonian and determines the mixing. Following the previous lattice QCD calculation of $\Xi_c$ and $\Xi_c'$, and estimating an off-diagonal matrix element, we extract the mixing angle between the $\Xi_c$ and $\Xi_c'$. Preliminary numerical results for the mixing angle confirm the previous observation that such mixing is incapable to explain the large SU(3) symmetry breaking in semileptonic decays of charmed baryons.

9.How robust are gravitational wave predictions from cosmological phase transitions?

Authors:Peter Athron, Lachlan Morris, Zhongxiu Xu

Abstract: Gravitational wave (GW) predictions of cosmological phase transitions are almost invariably evaluated at either the nucleation or percolation temperature. We investigate the effect of the transition temperature choice on GW predictions, for phase transitions with weak, intermediate and strong supercooling. We find that the peak amplitude of the GW signal varies by a factor of a few for weakly supercooled phase transitions, and by an order of magnitude for strongly supercooled phase transitions. The variation in amplitude for even weakly supercooled phase transitions can be several orders of magnitude if one uses the mean bubble separation, while the variation is milder if one uses the mean bubble radius instead. We also investigate the impact of various approximations used in GW predictions. Many of these approximations introduce at least a 10% error in the GW signal, with others introducing an error of over an order of magnitude.

10.Interactions between several types of cosmic strings

Authors:Kohei Fujikura, Siyao Li, Masahide Yamaguchi

Abstract: We study the interaction of several types of static straight cosmic strings, including local strings, global strings, and bosonic superconducting strings with and without magnetic currents. First, we evaluate the interaction energy of two widely separated cosmic strings using the point source formalism and show that the most dominant contribution to the interaction energy comes from the excitation of the lightest mediator particles in a underlying theory. The interaction energy at arbitrary separation distances is then analyzed numerically by the gradient flow method. It turns out that an additional scalar field introduced in the bosonic superconducting string becomes an additional source of attraction. For such a bosonic superconducting string, we find that a string with two winding numbers is energetically favorable compared to two strings with a single winding number in a certain parameter region. Our analysis reveals that a phase structure of bosonic superconducting strings is richer than that of local and global strings and that the formation of bound states at intersections of bosonic superconducting strings is favored.

11.Electromagnetic energy transfer processes in Effective Electro-Magneto Dynamics of axions

Authors:Andras Patkos

Abstract: Oscillating and dissipative energy exchange between the electromagnetic and axion fields is investigated in an effective electro-magneto dynamical (EEMD) model theory, implying the coexistence of axions with hypothetic magnetic charges. An exact formula is presented for the energy transfer between the electromagnetic and axionic sectors. In a first example we compute analytically the homogeneously oscillating electric and magnetic field configurations generated by the combined action of a constant static magnetic field and a periodically oscillating axion condensate. In the second example the electromagnetic radiative energy loss of a gravitationally bound axion configuration is computed in the EEMD model. As a result an asymptotic $\sim t^{1/5}$ temporal increase of the clump size is found also in EEMD.

12.Next-to-leading order QCD corrections to the form factors of $B$ to scalar meson decays

Authors:Xue-Ying Han, Long-Shun Lu, Cai-Dian Lü, Yue-Long Shen, Bo-Xuan Shi

Abstract: We calculate the next-to-leading order QCD corrections to $B\rightarrow S$ (scalar mesons) form factors from QCD light-cone sum rules with $B$ meson light-cone distribution amplitude. We demonstrate that the $B$ meson-to-vacuum correlation function can be factorized into the convolution of short-distance coefficients and light-cone distribution amplitude at the one-loop level and find that only $\phi_B^+(\omega)$ contributes to the form factors. We then employ the z-parameterization combined with constraints from strong coupling constants to reconstruct the $q^2$ dependence of the form factors in the whole kinematic allowed regions. Due to the large cancelations between the hard functions and the jet functions, the next-to-leading order results show a modest increase of approximately 5\% compared to the leading order results. Based on the results of form factors, we predict the branching ratios of semi-leptonic $B\rightarrow Sl\bar{\nu}$ and $B\rightarrow S\nu\bar{\nu}$ processes, as well as several angular observables, such as forward-backward asymmetries, "flat terms" and lepton polarization asymmetries. We compare these results with calculations from other methods. Experimental verification of these results is required in future experiments.

13.Axion Domain Walls, Small Instantons, and Non-Invertible Symmetry Breaking

Authors:Clay Cordova, Sungwoo Hong, Lian-Tao Wang

Abstract: Non-invertible global symmetry often predicts degeneracy in axion potentials and carries important information about the global form of the gauge group. When these symmetries are spontaneously broken they can lead to the formation of stable axion domain wall networks which support topological degrees of freedom on their worldvolume. Such non-invertible symmetries can be broken by embedding into appropriate larger UV gauge groups where small instanton contributions lift the vacuum degeneracy, and provide a possible solution to the domain wall problem. We explain these ideas in simple illustrative examples and then apply them to the Standard Model, whose gauge algebra and matter content are consistent with several possible global structures. Each possible global structure leads to different selection rules on the axion couplings, and various UV completions of the Standard Model lead to more specific relations. As a proof of principle, we also present an example of a UV embedding of the Standard Model which can solve the axion domain wall problem. The formation and annihilation of the long-lived axion domain walls can lead to observables, such as gravitational wave signals. Observing such signals, in combination with the axion coupling measurements, can provide valuable insight into the global structure of the Standard Model, as well as its UV completion.

1.Neutrino Phenomenology in a Model with Generalized CP symmetry within Type-I seesaw framework

Authors:Tapender, Sanjeev Kumar, Surender Verma

Abstract: We investigate the consequences of generalized CP (GCP) symmetry within the context of the two Higgs doublet model (2HDM), specifically focusing on the lepton sector. Utilizing the Type-I seesaw framework, we study an intriguing connection between the Dirac Yukawa couplings originating from both Higgs fields, leading to a reduction in the number of independent Yukawa couplings and simplifying the scalar and Yukawa sectors when compared to the general 2HDM. The CP3 constraint results in two right-handed neutrinos having equal masses and leads to a diagonal right-handed Majorana neutrino mass matrix. Notably, CP symmetry experiences a soft break due to the phase associated with the vacuum expectation value of the second Higgs doublet. The model aligns well with observed charged lepton masses and neutrino oscillation data, explaining both masses and mixing angles, and yields distinct predictions for normal and inverted neutrino mass hierarchies. It features a novel interplay between atmospheric mixing angle $\theta_{23}$ and neutrino mass hierarchy: the angle $\theta_{23}$ is below maximal for the normal hierarchy and above maximal for inverted hierarchy. Another interesting feature of the model is inherent CP violation for the inverted hierarchy.

2.Axion inflation in the strong-backreaction regime: decay of the Anber-Sorbo solution

Authors:Richard von Eckardstein, Marco Peloso, Kai Schmitz, Oleksandr Sobol, Lorenzo Sorbo

Abstract: Axion inflation coupled to Abelian gauge fields via a Chern-Simons-like term of the form $\phi F\tilde{F}$ represents an attractive inflationary model with a rich phenomenology, including the production of magnetic fields, black holes, gravitational waves, and the matter-antimatter asymmetry. In this work, we focus on a particular regime of axion inflation, the so-called Anber-Sorbo (AS) solution, in which the energy loss in the gauge-field production provides the dominant source of friction for the inflaton motion. We revisit the AS solution and confirm that it is unstable. Contrary to earlier numerical works that attempted to reach the AS solution starting from a regime of weak backreaction, we perform, for the first time, a numerical evolution starting directly from the regime of strong backreaction. Our analysis shows that, at least as long as one neglects spatial inhomogeneities in the inflaton field, the AS solution has no basin of attraction, not even a very small one that might have been missed in previous numerical studies. Our analysis employs an arsenal of analytical and numerical techniques, some established and some newly introduced, including (1) linear perturbation theory along the lines of arXiv:2209.08131, (2) the gradient expansion formalism (GEF) developed in arXiv:2109.01651, (3) a new linearized version of the GEF, and (4) the standard mode-by-mode approach in momentum space in combination with input from the GEF. All these methods yield consistent results confirming the instability of the AS solution, which renders the dynamics of axion inflation in the strong-backreaction regime even more interesting than previously believed.

3.Composite scalar bosons masses: Effective potential versus Bethe-Salpeter approach

Authors:A. Doff

Abstract: Ten years ago the $125$ GeV Higgs resonance was discovered at the LHC[1,2], if this boson is a fundamental particle or a particle composed of new strongly interacting particles is still an open question. If this is a composite boson there are still no signals of other possible composite states of this scheme, a possible solution to this problem was recently discussed in Refs.[30,31], where it is argued that the Higgs boson can be a composite dilaton [30]. In this work, considering an effective potential for composite operators we verify that the potential responsible for a light composite scalar boson of $O(120)GeV$, behaves like $\propto \Phi^4$ suggesting that if the Higgs boson is a composite scalar it may be a composite dilaton.

4.Phenomenological study of two minor zeros in neutrino mass matrix using trimaximal mixing

Authors:Iffat Ara Mazumder, Rupak Dutta

Abstract: We study the phenomenological implications of two minor zeros in neutrino mass matrix using trimaximal mixing matrix. In this context, we analyse fifteen possible cases of two minor zeros in neutrino mass matrix and found only two cases, namely class $A_1$ and class $A_2$, that are compatible with the present neutrino oscillation data. We present correlations of several neutrino oscillation parameters and give prediction of the total neutrino mass, the values of effective Majorana mass, the effective electron anti-neutrino mass and CP violating Majorana phases for these two classes. We also explore the degree of fine tuning in the elements of neutrino mass matrix. Moreover, We propose a flavor model within the seesaw model along with $Z_{8}$ symmetry group to generate these classes.

5.Global monopoles in the two-Higgs-doublet-model

Authors:Richard A. Battye, Steven J. Cotterill, Dominic G. Viatic

Abstract: We discuss monopoles formed due to the spontaneous breakdown of a global $SO(3)_{\rm HF}$ symmetry within the global two-Higgs doublet model. We explain that the Higgs sector dynamics can be described in terms of two vectors one of which is null, $R^A=(R^0,R^a,R^4,R^5)$ for $a=1,2,3$, with 5 independent components describing the Higgs family symmetry and another, $n^a$, with 3 independent components related to the ``would-be'' Goldstone bosons. When formed from random initial conditions we find that monopoles are formed with a charged vacuum in the centre which couples the two fields together. We find a spherical symmetric solution which is an approximately uniform, unit winding of the sphere in both the $R^a$ and $n^a$ vectors. These global monopoles are closely related to the Nambu monopole. The additional complexity and structure contained in these monopoles does not appear to prevent the scaling of their density.

6.Thermalization and isotropization in the AMY parton cascade ALPACA

Authors:Robin Törnkvist, Korinna Zapp

Abstract: We look at thermalization and isotropization processes in the newly introduced AMY QCD kinetic theory parton cascade ALPACA. For thermalization, we consider the case of overoccupied initial conditions, and study the time evolution of the distribution as it relaxes to thermal equilibrium. We find that the system thermalizes as expected compared to known analytical results. For anisotropic systems, we take a first look at the qualitative behaviour of isotropization for Color Glass Condensate-like initial conditions in a homogeneous box with periodic boundary conditions.

7.Small systems and the single-hit approximation in the AMY parton cascade ALPACA

Authors:Robin Törnkvist, Korinna Zapp

Abstract: Understanding how momentum anisotropies arise in small collision systems is important for a quantitative understanding of collectivity in terms of QCD dynamics in small and large collision systems. In this letter we present results for small collision systems from the newly developed parton cascade ALPACA, which faithfully encodes the AMY effective kinetic theory. ALPACA reproduces quantitatively previously know results from a calculation in the single-hit approximation for small values of the coupling. We discuss in detail how such a comparison is to be carried out. Particularly at larger coupling a generic differences between the two approaches becomes apparent, namely that in parton cascades particles interact over a finite distance while in direct integrations of the Boltzmann equation the interactions are local. This leads to quantitative differences in the extracted values for the elliptic flow coefficient, but also raises questions of a much more fundamental nature that are worth exploring in the future.

1.Insights from the magnetic field dependence of the muonium-to-antimuonium transition

Authors:Takeshi Fukuyama, Yukihiro Mimura, Yuichi Uesaka

Abstract: The muonium-to-antimuonium transition experiment is about to be updated. Notably, the experiment at J-PARC in Japan can explore the magnetic field dependence of the transition probability. In this paper, we investigate the information that we can extract from the transition probabilities across different magnetic field strengths, while also taking into account a planned transition experiment at CSNS in China. There are two model-independent parameters in the transition amplitude, and we ascertain the feasibility of determining these parameters, including their relative physical phase, from experimental measurements. This physical phase can be related to the electron electric dipole moment, which is severely constrained by experiments. The underlying mediator responsible for the transition can be either doubly charged particles or neutral particles. In the former case, typical magnetic fields yield specific probability ratios, while the latter presents a range of the probability ratio. We investigate several models with neutral mediators, and elucidate that the probability ratio is linked to the sign of new physics contribution to the electron $g-2$. The pivotal role of the J-PARC transition experiment in shedding light on these insights is emphasized.

2.Forward proton physics at LHC

Authors:Rafał Staszewski

Abstract: Diffractive phenomena constitute a large fraction of interactions occurring in pp collisions at LHC. Because of the non-perturbative nature, their present understanding is still relatively poor and uncertain. One of the methods to study these processes is forward proton tagging. I will discuss the mechanism of diffractive processes, recent results, and potential implications. The proton tagging method can also be used for measurements of photon-induced processes, in particular, the photon-photon interactions. I will present the physics behind these processes, the experimental status and the lessons we can learn for the strong interactions and for the electroweak sector.

3.Testing Lorentz invariance violation using cosmogenic neutrinos

Authors:M. A. Reyes, D. Boncioli, J. M. Carmona, J. L. Cortés

Abstract: Secondary messengers such as neutrinos and photons are expected to be produced in interactions of ultra-high-energy cosmic rays (UHECRs) with extragalactic background photons. Their propagation could be altered by the effects of Lorentz invariance violation. In this work, we have developed an extension of the SimProp code that includes some Lorentz-violating scenarios affecting the propagation of neutrinos. We present the corresponding expected cosmogenic neutrino fluxes for three different astrophysical scenarios for the production of UHECRs. These results can be used to put constraints on the scale of Lorentz violation in the neutrino sector.

4.Hadronization dynamics from the spectral representation of the gauge invariant quark propagator

Authors:Caroline S. R. Costa, Alberto Accardi, Andrea Signori

Abstract: Using the spectral representation of the quark propagator we study the Dirac decomposition of the gauge invariant quark propagator, whose imaginary part describes the hadronization of a quark as this interacts with the vacuum. We then demonstrate the formal gauge invariance of the so-called jet mass, that is of the coefficient of the chiral-odd part of the gauge invariant propagator, that can be expressed in any gauge as the first moment of the chiral-odd quark spectral function. This is therefore revealed to be a \textit{bona fide} QCD observable encoding aspects of the dynamical mass generation in the QCD vacuum, and is furthermore experimentally measurable in specific twist-3 longitudinal-transverse asymmetries in DIS and in semi-inclusive electron-positron collisions. In light-like axial gauges, we also obtain a new sum rule for the spectral function associated with the gauge fixing vector. We finally present a gauge-dependent formula that connects the second moment of the chiral-even coefficient of the quark spectral function to invariant mass generation and final state rescattering in the hadronization of a quark. Finding twist-4 experimental observables sensitive to this quantity is left for future work.

5.A POWHEG generator for deep inelastic scattering

Authors:Andrea Banfi, Silvia Ferrario Ravasio, Barbara Jäger, Alexander Karlberg, Felix Reichenbach, Giulia Zanderighi

Abstract: We present a new event generator for the simulation of both neutral- and charged-current deep inelastic scattering (DIS) at next-to-leading order in QCD matched to parton showers using the POWHEG method. Our implementation builds on the existing POWHEG BOX framework originally designed for hadron-hadron collisions, supplemented by considerable extensions to account for the genuinely different kinematics inherent to lepton-hadron collisions. In particular, we present new momentum mappings that conserve the special kinematics found in DIS, which we use to modify the POWHEG BOX implementation of the Frixione-Kunszt-Signer subtraction mechanism. We compare our predictions to fixed-order and resummed predictions, as well as to data from the HERA ep collider. Finally we study a few representative distributions for the upcoming Electron Ion Collider.

6.Dispersive analysis of the experimental data on the electromagnetic form factor of charged pions at spacelike momenta

Authors:S. Simula, L. Vittorio

Abstract: The experimental data on the electromagnetic form factor of charged pions available at spacelike momenta are analyzed using the Dispersive Matrix (DM) approach, which describes the momentum dependence of hadronic form factors without introducing any explicit parameterization and includes properly the constraints coming from unitarity and analyticity. The unitary bound is evaluated nonperturbatively making use of the results of lattice QCD simulations of suitable two-point correlation functions contributing to the HVP term of the muon. Thanks to the DM method we determine the pion charge radius from existing spacelike data in a completely model-independent way and consistently with the unitary bound, obtaining $< r_\pi >_{DM} = 0.703 \pm 0.027$ fm. This finding differs by $\simeq 1.6$ standard deviations from the latest PDG value $< r_\pi >_{PDG} = 0.659 \pm 0.004$ fm, which is dominated by the very precise results of dispersive analyses of timelike data coming from measurements of the cross section of the $e^+ e^- \to \pi^+ \pi^-$ process. We have analyzed the spacelike data using also traditional $z$-expansions, like the Boyd-Grinstein-Lebed (BGL) or Bourrely-Caprini-Lellouch (BCL) fitting functions and adopting a simple procedure that incorporates ab initio the non-perturbative unitary bound in the fitting process. We get $< r_\pi >_{BGL} = 0.711 \pm 0.039$ fm and $< r_\pi >_{BCL} = 0.709 \pm 0.028$ fm in nice agreement with the DM result. We have addressed also the issue of the onset of perturbative QCD by performing a sensitivity study of the pion form factor at large spacelike momenta, based only on experimental spacelike data and unitarity. Hence, although the leading pQCD behaviour is found to set in only at very large momenta, our DM bands may provide information about the pre-asymptotic effects related to the scale dependence of the pion distribution amplitude.

7.R&D for Positron Sources at High-Energy Lepton Colliders

Authors:Gudrid Moortgat-Pick, Sabine Riemann, Peter Sievers, Carmen Tenholt

Abstract: Several designs for high-energy Lepton Colliders serving as Higgs factories but extendable to higher energies up to the TeV range are under discussion. The most mature design is the International Linear Collider (ILC), but also the Compact Linear Collider (CLIC) as well as the new concept of a Hybrid Asymmetric Linear Higgs Factory (HALHF) have a large physics potential. The first energy stage with $\sqrt{s}=250$~GeV requires high luminosity and polarized beams and imposes an effort for all positron source designs at high-energy colliders. In the baseline design of the ILC, an undulator-based source is foreseen for the positron source in order to match the physics requirements. In this contribution an overview is given about the undulator-based source, the target tests, the rotating target wheel design, as well as the pulsed solenoid and the new technology development of plasma lenses as optic matching devices.

8.$T_{cs0}(2900)$ and $T_{c\bar{s}0}^a(2900)$ as the charmed strange partners of $T_{cc}(3875)$ and $Z_c(3900)$ and the prediction of more members

Authors:Bo Wang, Kan Chen, Lu Meng, Shi-Lin Zhu

Abstract: We relate the interactions of the $\bar{D}^{(\ast)} K^\ast$ and $D^{(\ast)} K^\ast$ systems to those of $D^{(\ast)}D^{(\ast)}$ and $D^{(\ast)}\bar{D}^{(\ast)}$ respectively, considering the residual strong interactions at the near-threshold energy is too weak to excite the strange quarks inside the hadrons. We propose an effective model to describe the low-energy S-wave interactions that are undertaken by the light $u$, $d$ quarks between two separated heavy hadrons. We find that the existence of molecules in the heavy-(anti)heavy sectors will naturally lead to the emergence of molecular states in $\bar{D}^{(\ast)} K^\ast$ and $D^{(\ast)} K^\ast$ systems. The recently observed $T_{cs0}(2900)$ and $T_{c\bar{s}0}^a(2900)$ can be well identified as the $0(0^+)$ and $1(0^+)$ partners of $T_{cc}(3875)$ and $Z_c(3900)$ in the charmed strange sector, respectively. We also predict their members under the {\it heavy} ($c$ and $s$) quark symmetry and SU(2) flavor symmetry. Most of them are very good molecule candidates, for example, (i) the $0(1^+)$ states in $D^\ast D^\ast$, $\bar{D}K^\ast$, $\bar{D}^\ast K^\ast$; (ii) the $0^{(+)}(2^{+(+)})$ states in $D^\ast \bar{D}^\ast$, $\bar{D}^\ast K^\ast$, $D^\ast K^\ast$; (iii) the $1^-(0^{++})$ state in $D^\ast\bar{D}^\ast$ and $1(1^+)$ state in $D^\ast K^\ast$. The $0^+(0^{++})$ state in $D\bar{D}$ and the $0(1^+)$ state in $DK^\ast$ might also exist as virtual states, and the $0(1^+)$ $DK^\ast$ can serve as a key to infer the existence of $0^+(0^{++})$ $D\bar{D}$. The $D_s\pi$ invariant mass spectrum of $T_{c\bar{s}0}^a(2900)$ is also studied within the coupled-channel approach, and the molecular interpretation of $T_{c\bar{s}0}^a(2900)$ is consistent with the experimental data. Searching for the predicted states in experiments is crucial to discriminate the different pictures for interpreting these near-threshold exotica.

9.Understanding the first measurement of $\mathcal{B}(B\to K ν \barν)$

Authors:Lukas Allwicher, Damir Becirevic, Gioacchino Piazza, Salvador Rosauro-Alcaraz, Olcyr Sumensari

Abstract: Recently, Belle II reported on the first measurement of $\mathcal{B}(B^\pm\to K^\pm \nu\bar{\nu})$ which appears to be almost $3\sigma$ larger than predicted in the Standard Model. We point out the important correlation with $\mathcal{B}(B\to K^{\ast} \nu\bar{\nu})$ so that the measurement of that decay mode could help restraining the possible options for building the model of New Physics. We then try to interpret this new experimental result in terms of physics beyond the Standard Model by using SMEFT and find that a scenario with coupling only to $\tau$ can accommodate the current experimental constraints but fails in getting a desired $R_{D^{(\ast )}}^\mathrm{exp}/R_{D^{(\ast )}}^\mathrm{SM}$, unless one turns the other SMEFT operators that are not related to $b\to s\ell\ell$ or/and $b\to s\nu\nu$.

10.Acceleration of a polarized neutron by its weak nuclear self-interaction

Authors:M. Donaire

Abstract: It is proven that the rotation of the spin of a polarized neutron is accompanied by a net nuclear force upon it. This force arises from the weak nuclear self-interaction of its constituent quarks, whose chiral nature induces the transfer of a net momentum to the fields of Z and W-bosons. This effect is linear in Fermi's constant. As a result, it is estimated that along the spin-flip of a polarized neutron its velocity undergoes a variation of the order of meters per second.

11.SU(3) Parity Doubling in Cold Neutron Star Matter

Authors:Eduardo S. Fraga, Rodrigo da Mata, Jürgen Schaffner-Bielich

Abstract: We present a phenomenological model to investigate the chiral phase transition characterized by parity doubling in dense, beta equilibrated, cold matter. Our model incorporates effective interactions constrained by SU(3) relations and considers baryonic degrees of freedom. By constraining the model with astrophysical data and nuclear matter properties, we find a first-order phase transition within realistic values of the slope parameter L. The inclusion of the baryon octet and negative parity partners, along with a chiral-invariant mass $m_{0}$, allows for a non-massless chiral symmetric phase. Through exploration of parameter space, we identify parameter sets satisfying mass and radius constraints without requiring a partonic phase. The appearance of the parity partner of the nucleon, the N(1535) resonance, suppresses strangeness, pushing hyperonization to higher densities. We observe a mild first-order phase transition to the chirally restored phase, governed by $m_{0}$. Our calculations of surface tension highlight its strong dependence on $m_{0}$. The existence of mixed phases is ruled out since they become energetically too costly. We compare stars with metastable and stable cores using both branches of the equation of state. Despite limited lifespans due to low surface tension values, phase conversion and star contraction could impact neutron stars with masses around 1.3 solar masses or more. We discuss some applications of this model in its non-zero temperatures generalization and scenarios beyond beta equilibrium that can provide insights into core-collapse supernovae, proto-neutron star evolution, and neutron star mergers. Core-collapse supernovae dynamics, influenced by chiral symmetry restoration and exotic hadronic states, affect explosion mechanisms and nucleosynthesis.

12.Majorana neutrinos in the triple gauge boson coupling $ZZZ^*$

Authors:Héctor Novales-Sánchez, Mónica Salinas

Abstract: Confirmed by the measurement of neutrino oscillations, neutrino mass is recognized as a genuine manifestation of physics beyond the Standard Model, while its originating mechanism remains a mystery. Moreover, the proper field-theory description of neutrinos, whether they are Majorana or Dirac type, must be linked to such a mechanism. The present work addresses the calculation, estimation, and analysis of one-loop contributions from virtual Majorana neutrinos, light and heavy as well, to the neutral gauge boson coupling $ZZZ$, which participates in $Z$-boson pair production from $e^+e^-$ collisions. This task is carried out in the framework defined by a seesaw variant in which light neutrinos remain massless at tree level, then becoming massive radiatively. The $ZZZ^*$ coupling, with $Z^*$ an off-shell $Z$ boson, is defined by two form factors, namely, $f_4$, characterizing CP-odd effects, and $f_5$, which is CP-even. Constraints from the Large Hadron Collider on both these quantities are currently ${\cal O}(10^{-4})$. Our calculation yields CP-nonpreserving contributions to $ZZZ$, which are absent in the framework of the sole Standard Model. Our estimations show that the $f_4$ contribution might be as large as ${\cal O}(10^{-7})$ for heavy-neutrino masses $\sim1\,{\rm TeV}$. CP-even contributions $f_5$ are also generated, which are, in general, larger than their CP-odd counterparts. We estimate them to be as large as ${\cal O}(10^{-4})$ at a center-of-mass energy of $500\,{\rm GeV}$, in $e^+e^-$ collisions.

1.Laplace Sum Rules in Quantum ChromoDynamics

Authors:Stephan Narison

Abstract: We shortly review some applications of the (inverse) Laplace (LSR) transform sum rules in Quantum ChromoDynamics (QCD) for extracting the fundamental QCD parameters (coupling constant $\alpha_s$, quark and gluon condensates) and the hadron properties (masses and decay constants). Links of LSR to some other forms of QCD spectral sum rules are also discussed. As prototype examples, we discuss in detail the $\rho$ and $\pi$ meson sum rules.

2.Probing Inelastic Dark Matter at the LHC, FASER and STCF

Authors:Chih-Ting Lu, Jianfeng Tu, Lei Wu

Abstract: In this work, we explore the potential of probing the inelastic dark matter (DM) model with an extra U(1)D gauge symmetry at the Large Hadron Collider, ForwArd Search ExpeRiment and Super Tau Charm Factory. To saturate the observed DM relic density, the mass splitting between two light dark states has to be small enough, and thus leads to some distinctive signatures at these colliders. By searching for the long-lived particle, the displaced muon-jets, the soft leptons, and the mono-photon events, we find that the inelastic DM mass in the range of 1 MeV to 210 GeV could be tested.

3.Interplay between improved particle rates and modified cosmological histories for dark matter

Authors:Simone Biondini

Abstract: A novel particle has been and still is an intriguing option to explain the strong evidence for dark matter in our universe. To quantitatively predict the dark matter energy density, two main ingredients are needed: particle rates and an expansion history of the universe. In this work, we explore the interplay between recent progress in the determination of particle production rates and modified cosmological histories. For the freeze-out mechanism, we focus on Sommerfeld and bound-state effects, which boost and make dark matter pair annihilation more efficient. As regards the freeze-in option, we include thermal masses, which enter the decay processes that produce dark matter, and we find that they can suppress or enhance the dark matter yield. We consider a class of modified cosmological histories that induce a faster universe expansion, and we assess their effect in combination with improved particle rates on the dark matter energy density.

4.Charming-loop contribution to $B_s\to γγ$ decay

Authors:Ilia Belov, Alexander Berezhnoy, Dmitri Melikhov

Abstract: We present a detailed theoretical study of nonfactorizable contributions of the charm-quark loop to the amplitude of the $B_s\to \gamma\,\gamma$ decay. This contribution involves the $B$-meson three-particle Bethe-Salpeter amplitude, $\langle 0|\bar s(y)G_{\mu\nu}(x)b(0)|\bar B_s(p)\rangle$, for which we take into account constraints from analyticity and continuity. The charming-loop contribution of interest may be described as a correction to the Wilson coefficient $C_{7\gamma}$, $C_{7\gamma}\to C_{7\gamma}(1+\delta C_{7\gamma})$. We calculate an explicit dependence of $\delta C_{7\gamma}$ on the parameter $\lambda_{B_s}$. Taking into account all theoretical uncertainties, $\delta C_{7\gamma}$ may be predicted with better than 10\% accuracy for any given value of $\lambda_{B_s}$. For our benchmark point $\lambda_{B_s}=0.45$ GeV, we obtain $\delta C_{7\gamma}=0.045\pm 0.004$. Presently, $\lambda_{B_s}$ is not known with high accuracy, but its value is expected to lie in the range $0.3\le \lambda_{B_s}({\rm GeV})\le 0.6$. The corresponding range of $\delta C_{7\gamma}$ is found to be $0.02\le \delta C_{7\gamma}\le 0.1$. One therefore expects the correction given by charming loops at the level of at least a few percent.

5.Monochromatic neutrinos from dark matter through the Higgs portal

Authors:Pablo de la Torre, Miguel Gutiérrez, Manuel Masip

Abstract: We define a minimal model of dark matter with a fermion singlet $\chi$ coupled to the visible sector through the Higgs portal and with a heavy Dirac neutrino $N$ that opens the annihilation channel $\chi \chi \to N \nu$. The model provides the observed relic abundance consistently with bounds from direct searches and implies a monochromatic neutrino signal at 10 GeV-1 TeV in indirect searches. In particular, we obtain the capture rate of $\chi$ by the Sun and show that the signal could be above the "neutrino floor" produced by cosmic rays showering in the solar surface. In most benchmark models this solar astrophysical background is above the expected dark matter signal, so the model that we propose is a canonical example of WIMP not excluded by direct searches that could be studied at neutrino telescopes and also at colliders.

6.Simultaneous detection of boosted dark matter and neutrinos from the semi-annihilation at DUNE

Authors:Mayumi Aoki, Takashi Toma

Abstract: Dark matter direct detection experiments impose the strong bounds on thermal dark matter scenarios. The bound can naturally be evaded if the cross section is momentum transfer dependent or velocity dependent. One can test such thermal dark matter scenarios if dark matter particles are boosted by some mechanism. In this work, we consider a specific semi-annihilation $\chi\chi\to \nu\overline{\chi}$ where $\chi$ ($\overline{\chi}$) is dark matter (anti-dark matter), and search for simultaneous detection of the neutrino and the boosted dark matter in the final state at DUNE. We find that the energies of the neutrino and boosted dark matter are reconstructed well due to the precise angular resolution of the DUNE detector. In addition, we find that both signals can be testable at DUNE if the dark matter mass is below 30 GeV, and the scattering cross section is momentum transfer dependent.

7.Correlation function for the $T_{bb}$ state: Determination of the binding, scattering lengths, effective ranges and molecular probabilities

Authors:A. Feijoo, L. R. Dai, L. M. Abreu, E. Oset

Abstract: We perform a study of the $B^{*+}B^0,B^{*0}B^+$ correlation functions using an extension of the local hidden gauge approach which provides the interaction from the exchange of light vector mesons and gives rise to a bound state of these components in $I=0$ with a binding energy of about $21$~MeV. After that, we face the inverse problem of determining the low energy observables, scattering length and effective range for each channel, the possible existence of a bound state, and, if found, the couplings of such a state to each $B^{*+}B^0,B^{*0}B^+$ component as well as the molecular probabilities of each of the channels. We use the bootstrap method to determine these magnitudes and find that, with errors in the correlation function typical of present experiments, we can determine all these magnitudes with acceptable precision. In addition, the size of the source function of the experiment from where the correlation functions are measured can be also determined with a high precision.

8.Improving NLO QCD event generators with high-energy EW corrections

Authors:Davide Pagani, Timea Vitos, Marco Zaro

Abstract: In this work we present a new approach for the combination of electroweak (EW) corrections at high energies, the so-called EW Sudakov logarithms (EWSL), and next-to-leading-order QCD predictions matched to parton-shower simulations (NLO+PS). Our approach is based on a reweighting procedure of NLO+PS events. In particular, both events with and without an extra hard emission from matrix elements are consistently reweighted via the inclusion of the corresponding EWSL contribution. We describe the technical details and the implementation in the MadGraph5_aMC@NLO framework. Via a completely automated procedure, events at this new level of accuracy can be obtained for a vast class of hadroproduction processes. As a byproduct we provide results for phenomenologically relevant physical distributions from top-quark pair and Higgs boson associated production ($t\overline{t}H$) and from the associated production of three $Z$ gauge bosons ($ZZZ$).

9.Feebly-interacting dark matter

Authors:G. Bélanger, S. Chakraborti, A. Pukhov

Abstract: We briefly review scenarios with feebly interacting particles (FIMPs) as dark matter candidates. The discussion covers issues with dark matter production in the early universe as well as signatures of FIMPs at the high energy and high intensity frontier as well as in astroparticle and cosmology.

10.Top Quark Mass Calibration for Monte Carlo Event Generators -- An Update

Authors:Bahman Dehnadi, André H. Hoang, Oliver L. Jin, Vicent Mateu

Abstract: We generalize and update our former top quark mass calibration framework for Monte Carlo (MC) event generators based on the $e^+e^-$ hadron-level 2-jettiness $\tau_2$ distribution in the resonance region for boosted $t\bar t$ production, that was used to relate the PYTHIA 8.205 top mass parameter $m_t^{\rm MC}$ to the MSR mass $m_t^{\rm MSR}(R)$ and the pole mass $m_t^{\rm pole}$. The current most precise direct top mass measurements specifically determine $m_t^{\rm MC}$. The updated framework includes the addition of the shape variables sum of jet masses $\tau_s$ and modified jet mass $\tau_m$, and the treatment of two more gap subtraction schemes to remove the ${\cal O}(\Lambda_{\rm QCD})$ renormalon related to large-angle soft radiation. These generalizations entail implementing a more versatile shape-function fit procedure and accounting for a certain type of $(m_t/Q)^2$ power corrections to achieve gap-scheme and observable independent results. The theoretical description employs boosted heavy-quark effective theory (bHQET) at next-to-next-to-logarithmic order (N$^2$LL), matched to soft-collinear effective theory (SCET) at N$^2$LL and full QCD at next-to-leading order (NLO), and includes the dominant top width effects. Furthermore, the software framework has been modernized to use standard file and event record formats. We update the top mass calibration results by applying the new framework to PYTHIA 8.205, HERWIG 7.2 and SHERPA 2.2.11. Even though the hadron-level resonance positions produced by the three generators differ significantly for the same top mass parameter $m_t^{\rm MC}$ value, the calibration shows that these differences arise from the hadronization modeling. Indeed, we find that $m_t^{\rm MC}$ agrees with $m_t^{\rm MSR}(1\,\mbox{GeV})$ within $200$ MeV for the three generators and differs from the pole mass by $350$ to $600$ MeV.

11.'Fat-brane' Universal Extra Dimension model confronted with the ATLAS multi-jet and photonic searches at 13 TeV LHC

Authors:Esra Akyumuk, Durmus Karabacak

Abstract: The current status of `fat-brane' minimal Universal Extra Dimensions (fat-mUED) is studied in the light of ATLAS experiment's recent reports. At the Large Hadron Collider (LHC) color charged first level Kaluza-Klein (KK) particles (first level excited quarks and gluons) can be abundantly pair-produced due to conserved quantity, viz., KK-parity, and strong interaction. The cascade decay of these particles to one or more Standard Model (SM) particle(s) and lighter first level KK particle(s) stops after producing the lightest excited massive state, named as the lightest KK particle (LKP). With the presence of gravity induced decays, stability of the LKP is lost and it may decay to photon or Z-boson by radiating KK-excited gravitons, hence leading to final state with photon(s) at the LHC. A variant signal topology is established when pair-produced first level colored KK particles undergo direct decay to an associated SM partner along with KK-excitations of graviton; thus leading to a signal with two hard jets and substantial missing energy. The ATLAS experiment lately reported two searches at 13 TeV LHC with 139 inverse-femtobarn of data; (i) multi-jet and (ii) photon and jets with missing energy. In both searches, the results showed no substantial deviation from the number of background events of the SM. Provided the absence of any number of excess events in both searches we constrained the parameters of the fat-mUED model, viz., the higher-dimensional Planck mass and the compactification scale.

12.ALP-Assisted Strong First-Order Electroweak Phase Transition and Baryogenesis

Authors:Keisuke Harigaya, Isaac R. Wang

Abstract: Axion-like particles (ALPs) can be naturally lighter than the electroweak scale. We consider an ALP that couples to the Standard Model Higgs to achieve the strong first-order electroweak phase transition. We discuss the two-field dynamics of the phase transition and the associated computation in detail and identify the viable parameter space. The ALP mass can be from the MeV to GeV scale. Baryon asymmetry can be explained by local baryogenesis without violating the electron electric dipole moment bound. The viable parameter space can be probed through Higgs exotic decay, rare kaon decay, the electron electric dipole moment, and the effective number of neutrinos in the cosmic microwave background. The gravitational-wave signal is too weak to be detected.

1.Probing the dipole portal to heavy neutral leptons via meson decays at the high-luminosity LHC

Authors:Daniele Barducci, Wei Liu, Arsenii Titov, Zeren Simon Wang, Yu Zhang

Abstract: We consider the dipole portal to sterile neutrinos, also called heavy neutral leptons (HNLs). The dipole interaction with the photon leads to HNL production in meson decays, as well as triggers the HNL decay into an active neutrino and a photon. HNLs with masses of order of 0.01-1 GeV are naturally long-lived if the dipole coupling is sufficiently small. We perform Monte-Carlo simulations and derive the sensitivities of the proposed FASER2 and FACET long-lived particle experiments to HNLs produced via the dipole operator in meson decays at the high-luminosity LHC. Our findings show that these future detectors will be complementary to each other, as well as to existing experiments, and will be able to probe new parts of the parameter space, especially in the case of the dipole operator coupled to the tau neutrino.

2.Revisit spin effects induced by thermal vorticity

Authors:Jian-Hua Gao, Shi-Zheng Yang

Abstract: We revisit the spin effects induced by thermal vorticity by calculating them directly from the spin-dependent distribution functions. For the spin-1/2 particles, we give the polarization up to the first order of thermal vorticity and compare it with the usual result calculated from the spin vector. For the spin-1 particles, we give the spin alignment in terms of thermal vorticity. Although the spin alignment receives only second-order contribution from thermal vorticity, we find that some non-diagonal elements in spin density matrix can receive first order contribution. We also find that the spin effects for both Dirac and vector particles will receive extra contribution when the spin direction is associated with the particle's momentum.

3.Effects of the $α$-cluster structure and the intrinsic momentum component of nuclei on the longitudinal asymmetry in relativistic heavy-ion collisions

Authors:Ru-XIn Cao, Song Zhang, Yu-Gang Ma

Abstract: The longitudinal asymmetry in relativistic heavy-ion collisions arises from the fluctuation in the number of participating nucleons. This asymmetry causes a rapidity shift in the center of mass of the participant zone. Both the rapidity shift and the longitudinal asymmetry have been found to be significant at the top LHC energy for collisions of identical nuclei. However, much discussion of the longitudinal asymmetry has treated the initial condition as a non-zero momentum only contributed only by the number of participants, i.e., the asymmetry depends only on the number of participating nucleons. In this work, we consider other effects on the longitudinal asymmetry other than fluctuation in the number of participants, e.g. the intrinsic momentum distribution as well as $\alpha$-clustering structure in the target or projectile nuclei for the collisions in the framework of a multiphase transport (AMPT) model. By introducing systems with different $\alpha$-clustering structure and intrinsic momentum distribution, we calculated ratio of different systems' rapidity distribution and extracted expansion coefficient to analyze the difference contributed by these factors. And we investigated the possible effect of non-Gaussian distribution on the rapidity distribution. These results may help us to constrain the initial conditions in ultra-relativistic heavy-ion collisions, and suggest a quantitative correction on final state measurement and a possible correlation between the initial condition and the final-state observable in LHC and RHIC energy.

4.Like-Sign W-Boson Scattering at the LHC -- Approximations and Full Next-to-Leading-Order Predictions

Authors:Stefan Dittmaier, Philipp Maierhöfer, Christopher Schwan, Ramon Winterhalder

Abstract: We present a new calculation of next-to-leading-order corrections of the strong and electroweak interactions to like-sign W-boson scattering at the Large Hadron Collider, implemented in the Monte Carlo integrator Bonsay. The calculation includes leptonic decays of the $\mathrm{W}$ bosons. It comprises the whole tower of next-to-leading-order contributions to the cross section, which scale like $\alpha_\mathrm{s}^3\alpha^4$, $\alpha_\mathrm{s}^2\alpha^5$, $\alpha_\mathrm{s}\alpha^6$, and $\alpha^7$ in the strong and electroweak couplings $\alpha_\mathrm{s}$ and $\alpha$. We present a detailed survey of numerical results confirming the occurrence of large pure electroweak corrections of the order of $\sim-12\%$ for integrated cross sections and even larger corrections in high-energy tails of distributions. The electroweak corrections account for the major part of the complete next-to-leading-order correction, which amounts to $15{-}20\%$ in size, depending on the details of the event selection chosen for analysing vector-boson-scattering. Moreover, we compare the full next-to-leading-order corrections to approximate results based on the neglect of contributions that are not enhanced by the vector-boson scattering kinematics (VBS approximation) and on resonance expansions for the $\mathrm{W}$-boson decays (double-pole approximation); the quality of this approximation is good within $\sim 1.5\%$ for integrated cross sections and the dominating parts of the differential distributions. Finally, for the leading-order predictions, we construct different versions of effective vector-boson approximations, which are based on cross-section contributions that are enhanced by collinear emission of $\mathrm{W}$ bosons off the initial-state (anti)quarks; in line with previous findings in the literature, it turns out that the approximative quality is rather limited for applications at the LHC.

5.Mapping QGP properties in Pb--Pb and Xe--Xe collisions at the LHC

Authors:L. Vermunt, Y. Seemann, A. Dubla, S. Floerchinger, E. Grossi, A. Kirchner, S. Masciocchi, I. Selyuzhenkov

Abstract: A phenomenological analysis of the experimental measurements of transverse momentum spectra of identified charged hadrons and strange hyperons in \PbPb and \XeXe collisions at the LHC is presented. The analysis is based on the relativistic fluid dynamics description implemented in the numerically efficient \fluidum approach. Building on our previous work, we separate in our treatment the chemical and kinetic freeze-out, and incorporate the partial chemical equilibrium to describe the late stages of the collision evolution. This analysis makes use of Bayesian inference to determine key parameters of the QGP evolution and its properties including the shear and bulk viscosity to entropy ratios, the initialisation time, the initial entropy density, and the freeze-out temperatures. The physics parameters and their posterior probabilities are extracted using a global search in multidimensional space with modern machine learning tools, such as ensembles of neural networks. We employ our newly developed fast framework to assess systematic uncertainties in the extracted model parameters by systematically varying key components of our analysis.

6.Hybrid Renormalization for Quasi Distribution Amplitudes of A Light Baryon

Authors:Chao Han, Yushan Su, Wei Wang, Jia-Lu Zhang

Abstract: We develop a hybrid scheme to renormalize quasi distribution amplitudes of a light baryon on the lattice, which combines the self-renormalization and ratio scheme. By employing self-renormalization, the UV divergences and linear divergence at large spatial separations in quasi distribution amplitudes are removed without introducing extra nonperturbative effects, while making a ratio with respect to the zero-momentum matrix element can properly remove the UV divergences in small spatial separations. As a specific application, distribution amplitudes of the $\Lambda$ baryon made of $uds$ are investigated, and the requisite equal-time correlators, which define quasi distribution amplitudes in coordinate space, are perturbatively calculated up to the next-to-leading order in strong coupling constant $\alpha_s$. These perturbative equal-time correlators are used to convert lattice QCD matrix elements to the continuum space during the renormalization process. Subsequently, quasi distribution amplitudes are matched onto lightcone distribution amplitudes by integrating out hard modes and the corresponding hard kernels are derived up to next-to-leading order in $\alpha_s$ including the hybrid counterterms. These results are valuable in the lattice-based investigation of the lightcone distribution amplitudes of a light baryon from the first principles of QCD.

7.Resonance contributions to nucleon spin structure in Holographic QCD

Authors:Francesco Bigazzi, Federico Castellani

Abstract: We study polarized inelastic electron-nucleon scattering at low momentum transfer, in the Witten-Sakai-Sugimoto model of holographic QCD. We focus in particular on resonance production contributions to the nucleon spin structure functions. Our analysis includes both spin $3/2$ and spin $1/2$ low-lying nucleon resonances with positive and negative parity. We determine, in turn, the helicity amplitudes for nucleon-resonance transitions and the resonance contributions to the neutron and proton generalized spin polarizabilities. Extrapolating the model parameters to realistic QCD data, our analysis, triggered by recent experimental results from Jefferson Lab, agrees with the observation that the $\Delta(1232)$ resonance gives the dominant contribution to the forward spin polarizabilities at low momentum transfer. The contribution is negative and increases towards zero as the momentum transfer increases. As expected, the contribution of the $\Delta(1232)$ to the longitudinal-transverse polarizabilities is instead negligible. Our analysis shows that different spin $1/2$ resonances give different contributions, in sign and magnitude, to the generalized longitudinal-transverse spin polarizabilities. In the proton case they globally give rise to a positive function which decreases towards zero as the momentum transfer increases. In the neutron case, the net effect produces a negative increasing function. These features are in qualitative agreement with experimental data.

8.Probing Neutral Triple Gauge Couplings with $Z^* γ\, (ν\bar ν γ)$ Production at Hadron Colliders

Authors:John Ellis, Hong-Jian He, Rui-Qing Xiao

Abstract: We study probes of neutral triple gauge couplings (nTGCs) via $Z^*\gamma$ production followed by off-shell decays $Z^*\to\nu\bar{\nu}$ at the LHC and future $pp$ colliders, including both CP-conserving (CPC) and CP-violating (CPV) couplings. We present the dimension-8 SMEFT operators contributing to nTGCs and derive the correct form factor formulation for the off-shell vertices $Z^*\gamma V^*$ ($V=Z,\gamma$) by matching them with the dimension-8 SMEFT operators. Our analysis includes new contributions enhanced by the large off-shell momentum of $Z^*$, beyond those of the conventional $Z\gamma V^*$ vertices with on-shell $Z\gamma$. We analyze the sensitivity reaches for probing the CPC/CPV nTGC form factors and the new physics scales of the dimension-8 nTGC operators at the LHC and future 100TeV $pp$ colliders. We also compare our predictions with the existing LHC measurements of CPC nTGCs in the $\nu\bar{\nu}\gamma$ channel.

9.Distinguishing models with $μ\to e $ observables

Authors:Marco Ardu, Sacha Davidson, Stéphane Lavignac

Abstract: Upcoming experiments will improve the reach for the lepton flavour violating (LFV) processes $\mu \to e \gamma$, $\mu \to e \bar{e} e$ and $\mu A \to e A$ by orders of magnitude. We investigate whether this upcoming data could rule out some popular TeV-scale LFV models (the type II seesaw, the inverse seesaw and a scalar leptoquark) using a bottom-up EFT approach involving twelve Wilson coefficients that can in principle all be determined by experimental measurements. In this 12-dimensional coefficient space, each model can only predict points in a specific subspace; for instance, flavour change involving singlet electrons is suppressed in the seesaw models, and the leptoquark induces negligible coefficients for 4-lepton scalar operators. Using the fact that none of these models can populate the whole region accessible to upcoming experiments, we show that $\mu \to e$ experiments have the ability to rule them out.

10.Eclectic flavor group $Δ(27)\rtimes S_3$ and lepton model building

Authors:Cai-Chang Li, Gui-Jun Ding

Abstract: We have performed a systematical study of the eclectic flavor group $\Delta(27)\rtimes S_3$ which is the extension of the traditional flavor symmetry $\Delta(27)$ by the modular symmetry group $S_3$. Consistency between $\Delta(27)$ and $S_3$ requires that the eight nontrivial singlet representations of $\Delta(27)$ should be arranged into four reducible doublets. The modular transformation matrices are determined for various $\Delta(27)$ multiplets, and the generalized CP symmetry compatible with $\Delta(27)\rtimes S_3$ are discussed. We study the general form of the K\"ahler potential and superpotential invariant under $\Delta(27)\rtimes S_3$, and the corresponding fermion mass matrices are presented. We propose a bottom-up model for lepton masses and mixing based on $\Delta(27)\rtimes S_{3}$, a numerical analysis is performed and the experimental data can be accommodated.

11.$K^-\toπ^- a$ at Next-to-Leading Order in Chiral Perturbation Theory

Authors:Claudia Cornella, Anne Mareike Galda, Matthias Neubert, Daniel Wyler

Abstract: The weak decay $K^-\to\pi^- a$ is a powerful probe of axion-like particles (ALPs). In this work, we provide a comprehensive analysis of this process within chiral perturbation theory, extending existing calculations by including complete next-to-leading order (NLO) contributions and isospin-breaking corrections at first order in $(m_u-m_d)$. We show that the consistent incorporation of ALPs in the QCD and weak chiral Lagrangians requires a non-trivial extension of the corresponding operator bases, which we describe in detail. Furthermore, we show that in the presence of an ALP the so-called weak mass term, which is unobservable in the Standard Model, is non-redundant already at leading order. We find that NLO corrections associated with flavor-violating ALP couplings modify the leading-order result by a few percent, with only small uncertainties. On the contrary, the NLO corrections proportional to flavor-conserving ALP couplings lead to an $\mathcal{O}(20\%)$ reduction relative to the leading-order predictions. These corrections are accompanied by a large uncertainties mainly originating from the QCD low-energy constant $L_{4,r}$ as well as from the presence of various unknown weak low-energy constants. We emphasize the importance of a precise determination of these coupling parameters for the successful study of new physics in light meson decays.

1.Fluctuations and correlations of baryonic chiral partners

Authors:Volker Koch, Michał Marczenko, Krzysztof Redlich, Chihiro Sasaki

Abstract: Fluctuations and correlations of the net-baryon number play an important role in exploring critical phenomena in phase transitions of strongly interacting matter governed by Quantum chromodynamics (QCD). In this work, we use the parity doublet model to investigate the fluctuations of the net-baryon number density in hot and dense hadronic matter. The model accounts for chiral criticality within the mean-field approximation. We focus on the qualitative properties and systematics of the first- and second-order susceptibility of the net-baryon number density, and their ratios for nucleons of positive and negative parity, as well as their correlator. We show that the fluctuations of the positive-parity nucleon do not necessarily reflect the fluctuations of the total net-baryon number density at the phase boundary of the chiral phase transition. We also investigate the non-trivial structure of the correlator. Furthermore, we discuss and quantify the differences between the fluctuations of the net-baryon number density in the vicinity of the chiral and liquid-gas phase transition in nuclear matter. We indicate a possible relevance of our results with the interpretation of the experimental data on net-proton number fluctuations in heavy-ion collisions.

2.Higgs Probes of axion-like particles

Authors:Masashi Aiko, Motoi Endo

Abstract: We study axion-like particle contributions to the Higgs boson decays. The particle is assumed to couple with the standard model electroweak gauge bosons. Although direct productions of axion-like particles have often been discussed, we investigate indirect contributions to the Higgs boson decays into fermions, photons, $W$, and $Z$ bosons at the one-loop level. It is found that the corrections to the fermions are suppressed, whereas precise measurements of the di-photon channel of the Higgs boson decay can provide a significant probe of the model especially when the axion-like particle is heavy and its coupling to di-photon is suppressed.

3.Approximate Bound State Solutions of the Fractional Schrödinger Equation under the Spin-Spin-Dependent Cornell Potential

Authors:M. Abu-Shady, E. Omugbe, E. P. Inyang

Abstract: In this work, the approximate bound state solutions of the fractional Schr\"odinger equation under a spin-spin-dependent Cornell potential are obtained via the convectional Nikiforov-Uvarov approach. The energy spectra are applied to obtain the mass spectra of the heavy mesons such as bottomonium, charmonium and bottom-charm. The masses for the singlet and triplet spin numbers increase as the quantum numbers increase. The fractional Schr\"odinger equation improves the mass spectra compared to the masses obtained in the existing literature. The bottomonium masses agree with the experimental data of the Particle Data Group where percentage errors for fractional parameters of \b{eta}=1,{\alpha}=0.97 and \b{eta}=1,{\alpha}=0.50 were found to be 0.67% and 0.49% respectively. The respective percentage errors of 1.97% and 1.62% for fractional parameters of \b{eta}=1,{\alpha}=0.97 and \b{eta}=1,{\alpha}=0.50 were obtained for charmonium meson. The results indicate that the potential curves coupled with the fractional parameters account for the short-range gluon exchange between the quark-antiquark interactions and the linear confinement phenomena which is associated with the quantum chromo-dynamic and phenomenological potential models in particle and high-energy physics

4.Shedding light on neutrino self-interactions with solar antineutrino searches

Authors:Quan-feng Wu, Xun-Jie Xu

Abstract: Solar antineutrinos are absent in the standard solar model prediction. Consequently, solar antineutrino searches emerge as a powerful tool to probe new physics capable of converting neutrinos into antineutrinos. In this study, we highlight that neutrino self-interactions, recently gaining considerable attention due to their cosmological and astrophysical implications, can lead to significant solar antineutrino production. We systematically explore various types of four-fermion effective operators and light scalar mediators for neutrino self-interactions. By estimating the energy spectra and event rates of solar antineutrinos at prospective neutrino detectors such as JUNO, Hyper-Kamiokande, and THEIA, we reveal that solar antineutrino searches can impose stringent constraints on neutrino self-interactions and probe the parameter space favored by the Hubble tension.

5.Refined renormalization group improvement for thermally resummed effective potential

Authors:Koichi Funakubo, Eibun Senaha

Abstract: We newly develop a renormalization group (RG) improvement for thermally resummed effective potentials. In this method, $\beta$-functions are consistently defined in resummed perturbation theories, so that order-by-order RG invariance is not spoiled after thermal resummation. With this improvement, scale dependences of phase transition quantities such as a critical temperature, which are known to be notoriously large at the one-loop order, are greatly reduced compared to calculations with the conventional $\overline{\text{MS}}$ scheme. By taking advantage of the RG invariance, we also devise a resummation method that can incorporate potentially harmful large logarithmic terms and temperature-dependent power corrections in a generic form. We point out that a resummed one-loop effective potential refined by the method can give results that agree with those obtained by resummed two-loop effective potentials within errors.

6.A new observable for $W$-mass determination

Authors:Luca Rottoli, Paolo Torrielli, Alessandro Vicini

Abstract: In this contribution we discuss the properties of the jacobian asymmetry, the new observable introduced in hep-ph/2301.04059 for a robust determination of the value and uncertainty of the $W$-boson mass at hadron colliders.

7.Isospectrality and configurational entropy as testing tools for bottom-up AdS/QCD

Authors:Miguel Angel Martin Contreras, Alfredo Vega, Saulo Diles

Abstract: This work discusses the connection between isospectrality and configurational entropy in holographic bottom-up models. We analyze the effect of monoparametric isospectral transformation in holographic decay constants and configurational entropy for a set of softwall-like models at zero temperature. We conclude that the isospectral parameter $\lambda$ defines a window of possible holographic models suitable to describe spectroscopy.

8.Neutrino constraints on inelastic dark matter captured in the Sun

Authors:Bhavesh Chauhan, Mary Hall Reno, Carsten Rott, Ina Sarcevic

Abstract: The flux of neutrinos from annihilation of gravitationally captured dark matter in the Sun has significant constraints from direct-detection experiments. However, these constraints are relaxed for inelastic dark matter as inelastic dark matter interactions generate less energetic nuclear recoils compared to elastic dark matter interactions. In this paper, we explore the possibility for large volume underground neutrino experiments to detect the neutrino flux from captured inelastic dark matter in the Sun. The neutrino spectrum has two components: a mono-energetic "spike" from pion and kaon decays at rest and a broad-spectrum "shoulder" from prompt primary meson decays. We focus on detecting the shoulder neutrinos from annihilation of hadrophilic inelastic dark matter with masses in the range 4-100 GeV and the mass splittings in up to 300 keV. We determine the event selection criterion for DUNE to identify GeV-scale muon neutrinos and anti-neutrinos originating from hadrophilic dark matter annihilation in the Sun, and forecast the sensitivity from contained events. We also map the current bounds from Super-Kamiokande and IceCube on elastic dark matter, as well as the projected limits from Hyper-Kamiokande, to the parameter space of inelastic dark matter. We find that there is a region of parameter space that these neutrino experiments are more sensitive to than the direct-detection experiments. For dark matter annihilation to heavy-quarks, the projected sensitivity of DUNE is weaker than current (future) Super (Hyper) Kamiokande experiments. However, for the light-quark channel, only the spike is observable and DUNE will be the most sensitive experiment.

9.On the oscillating electric dipole moment induced by axion-fermion couplings

Authors:Luca Di Luzio, Hector Gisbert, Philip Sørensen

Abstract: It has been recently claimed that the axion coupling to fermions is responsible for an oscillating electric dipole moment (EDM) in the background of axion dark matter. In this work, we re-examine the derivation of this effect. Contrary to previous studies, we point out the physical relevance of an axion boundary term, which is crucial in restoring the axion shift symmetry and drastically affects the EDM phenomenology. To describe the latter, we introduce the notion of a time-integrated effective axion EDM, which encodes the boundary term and whose magnitude depends on the oscillating regime. For slow oscillations the boundary term washes out the standard oscillating EDM, resulting in an exact cancellation in the static limit. Conversely, during fast oscillations, the boundary term amplifies the effective EDM. This new observable is especially interesting in the case of the electron EDM. Remarkably, for an $\mathcal{O}(1)$ axion-electron coupling, the overall size of the effective EDM in the intermediate oscillations regime is comparable to the present static EDM limit.

1.Octant Degeneracy and Plots of Parameter Degeneracy in Neutrino Oscillations Revisited

Authors:Sho Sugama, Osamu Yasuda

Abstract: The three kinds of parameter degeneracy in neutrino oscillation, the intrinsic, sign and octant degeneracy, form an eight-fold degeneracy. The nature of this eight-fold degeneracy can be visualized on the ($\sin^22\theta_{13}$, $1/\sin^2\theta_{23}$)-plane, through quadratic curves defined by $P(\nu_\mu\to\nu_e)=$ const. and $P(\bar{\nu}_\mu\to\bar{\nu}_e)=$ const., along with a straight line $P(\nu_\mu\to\nu_\mu)=$ const. After $\theta_{13}$ was determined by reactor neutrino experiments, the intrinsic degeneracy in $\theta_{13}$ transforms into an alternative octant degeneracy in $\theta_{23}$, which can potentially be resolved by incorporating the value of $P(\nu_\mu\to\nu_\mu)$. In this paper, we analytically discuss whether this octant parameter degeneracy is resolved or persists in the future long baseline accelerator neutrino experiments, such as T2HK, DUNE, T2HKK and ESS$\nu$SB. It is found that the energy spectra near the first oscillation maximum are effective in resolving the octant degeneracy, whereas those near the second oscillation maximum are not.

2.$J/ψ$ and $ψ$(2S) polarization in proton-proton collisions at the LHC energies using PYTHIA8

Authors:Bhagyarathi Sahoo, Dushmanta Sahu, Suman Deb, Captain R. Singh, Raghunath Sahoo

Abstract: The production mechanisms of charmonium states in both hadronic and heavy-ion collisions hold great significance for investigating the hot and dense QCD matter. Studying charmonium polarization in ultra-relativistic collisions can also provide insights into the underlying production mechanisms. With this motivation, we explore the $J/\psi$ and $\psi$(2S) polarization in proton+proton collisions at $\sqrt{s}$ = 7, 8, and 13 TeV using a pQCD-inspired Monte-Carlo event generator called PYTHIA8. This work considers reconstructed quarkonia through their dimuons decay channel in the ALICE forward rapidity acceptance range of $2.5 < y_{\mu \mu} < 4$. Further, we calculate the polarization parameters $\lambda_{\theta}$, $\lambda_{\phi}$, $\lambda_{\theta \phi}$ from the polar and azimuthal angular distributions of the dimuons in helicity and Collins-Soper frames. This study presents a comprehensive measurement of the polarization parameters as a function of transverse momentum, charged-particle multiplicity, and rapidity at the LHC energies. Our findings of charmonium polarization are in qualitative agreement with the corresponding experimental data.

3.New type of doubly charmed molecular pentaquarks containing most strange quarks: Mass spectra, radiative decays, and magnetic moments

Authors:Fu-Lai Wang, Xiang Liu

Abstract: In this work, we first study the mass spectra of the $\Omega_{c}^{(*)}{D}_s^{(*)}$-type doubly charmed molecular pentaquark candidates, where the one-boson-exchange model is adopted by considering both the $S$-$D$ wave mixing effect and the coupled channel effect. Our findings indicate that the $\Omega_{c}{D}_s^*$ state with $J^P={1}/{2}^{-}$, the $\Omega_{c}^*{D}_s^*$ state with $J^P={1}/{2}^{-}$, and the $\Omega_{c}^*{D}_s^*$ state with $J^P={3}/{2}^{-}$ can be considered as the most promising doubly charmed molecular pentaquark candidates, and the $\Omega_{c}{D}_s$ state with $J^P={1}/{2}^{-}$, the $\Omega_{c}^*{D}_s$ state with $J^P={3}/{2}^{-}$, and the $\Omega_{c}{D}_s^*$ state with $J^P={3}/{2}^{-}$ are the possible doubly charmed molecular pentaquark candidates. Furthermore, we further explore the radiative decays and the magnetic moments of the most promising doubly charmed molecular pentaquark candidates in the constituent quark model. As a crucial aspect of spectroscopy, the information of the radiative decays and the magnetic moments can provide the valuable clues to reflect their inner structures. With the accumulation of higher statistical data at the Large Hadron Collider, we propose that the LHCb Collaboration should focus on the problem of searching for these predicted doubly charmed molecular pentaquark candidates containing most strange quarks in the coming years.

4.Constraining Axion and ALP Dark Matter from Misalignment during Reheating

Authors:Yong Xu

Abstract: We explore the phenomenology of QCD axion and axion-like particle (ALP) dark matter production via misalignment during inflationary reheating. We investigate scenarios involving inflaton oscillating in a generic potential $\sim \phi^n$, considering inflaton decay and annihilation for reheating. For low reheating temperatures, the parameter space leading to the correct relic abundance can be enlarged beyond the standard case. Depending on the type of inflaton-matter couplings and the value of $n$, we find that certain parts of the extended parameter space are already constrained by ADMX, CAPP, and MUSE experiments. Future Haloscope experiments are expected to impose stringent constraints. We highlight the potential to utilize axion experiments in constraining the dynamics of reheating.

5.Simulation of 3+1D glasma in Milne coordinates I: Development of the framework

Authors:Hidefumi Matsuda, Xu-Guang Huang

Abstract: We propose a new numerical method for $3+1$D glasma simulation using Milne coordinates. We formulate the classical Yang-Mills field and $3$D classical color current on a lattice at the initial proper time, specified as a moment just before the collision of the two nuclei. By solving the evolution equations, we extract observables of the $3$D glasma at later times. We demonstrate the efficiency of our method in terms of numerical cost and apply it to the central collisions of Au-Au. We also discuss possible further improvements of our method.

6.Muon precession from the aspect of Dirac equations

Authors:Jinbo He, Lei Ming, Yi-Lei Tang, Qiankang Wang, Hong-Hao Zhang

Abstract: In this paper, we would like to compute the muon anomalous precession frequency through solving the wave functions of the Dirac equations straightforwardly. The precession of a (anti-)muon with an anomalous magnetic momentum term is calculated together with the quantum corrections. Lorentz violation terms up to the lowest non-trivial order is introduced, and their effects on anomalous precession are evaluated perturbatively.

7.Pionic and radiative transitions from $T_{c\bar{s}0}^+(2900)$ to $D_{s1}^+(2460)$ as a probe of the structure of $D_{s1}^+(2460)$

Authors:Zi-Li Yue, Cheng-Jian Xiao, Dian-Yong Chen

Abstract: In this work, we evaluated the widths of the pionic and radiative transitions from the $T_{c\bar{s}0}^{+}(2900)$ to the $D_{s1}^{+}(2460)$ in the $D_{s1}^{+}(2460)$ molecular frame and the $D_{s1}^{+}(2460)$ charmed-strange meson frame. Our estimations demonstrate that the transition widths in the $D_{s1}^{+}(2460)$ molecular frame are much larger than those in the the $D_{s1}^{+}(2460)$ charmed-strange meson frame. Specifically, the ratio of the widths of $\Gamma(T_{c\bar{s}0}^{+}(2900)\to D_{s1}^{+} \pi^{0})$ and $\Gamma(T_{c\bar{s}0}^{+}(2900)\to D^{+(0)}K^{0(+)})$ is estimated to be around 0.1 in the $D_{s1}^{+}(2460)$ charmed-strange meson frame, whereas the lower limit of this ratio is 0.67 in the $D_{s1}^{+}(2460)$ molecular frame. Thus, the aforementioned ratio could be employed as a tool for testing the nature of the $D_{s1}^{+}(2460)$.

8.Unraveling anomalies in Deeply Virtual Compton Scattering

Authors:Shohini Bhattacharya, Yoshitaka Hatta, Werner Vogelsang

Abstract: We calculate the one-loop quark box diagrams relevant to polarized and unpolarized Deeply Virtual Compton Scattering by introducing an off-forward momentum $l^\mu$ as an infrared regulator. This regularization approach allows us to reveal the poles associated with the chiral anomaly in the polarized scenario, as well as the trace anomaly in the unpolarized case. We provide an interpretation of our findings in the context of pertinent Generalized Parton Distributions (GPDs). Furthermore, we discuss the implications of these poles on the QCD factorization pertaining to Compton amplitudes.

9.Non-thermal WIMP Production from Higher Order Moduli Decay

Authors:Amitayus Banik, Manuel Drees

Abstract: In a non-standard cosmological scenario, heavy, long-lived particles, which we call moduli, dominate the energy density prior to Big Bang Nucleosynthesis. Weakly Interacting Massive Particles (WIMPs) may be produced non-thermally from moduli decays. The final relic abundance then depends on additional parameters such as the branching ratio of moduli to WIMPs and the modulus mass. This is of interest for WIMP candidates, such as a bino-like neutralino, where thermal production in standard cosmology leads to an overdensity. Previous works have shown that the correct dark matter (DM) relic density can then still be obtained if the moduli, with mass less than $10^{7}$ GeV, decay to WIMPs with a branching ratio of less than $10^{-4}$. This upper bound could easily be violated once higher order corrections, involving final states with more than two particles, are included. We compute the branching ratios of three- and four-body decays of a modulus into final states involving two DM particles for general couplings. We then apply these expressions to sparticle production within the Minimal Supersymmetric Standard Model (MSSM) with neutralino DM. We find that this upper bound on the branching ratio can be satisfied in simplified models through an appropriate choice of as yet undetermined couplings. However, in the MSSM, it requires sparticle masses to be very close to half the modulus mass, in contrast to the idea of weak-scale supersymmetry.

10.Third order QCD predictions for fiducial W-boson production

Authors:John Campbell, Tobias Neumann

Abstract: Measurements of W-boson production at the LHC have reached percent-level precision and impose challenging demands on theoretical predictions. Such predictions directly limit the precision of measurements of fundamental quantities such as the W-boson mass and the weak mixing angle. A dominant source of uncertainty in predictions is from higher-order QCD effects. We present a calculation of W-boson production at the level of $\alpha_s^3$ at fixed order and including transverse-momentum resummation. We further show predictions for a direct comparison with low-pileup ATLAS transverse-momentum and fiducial cross-section measurements at $\sqrt{s}=5.02\text{ TeV}$. We discuss in detail the impact of modern PDFs. Our calculation including the matching to W+jet production at NNLO will be publicly available the upcoming CuTe-MCFM release and allows for theory-data comparison at the state-of-the-art level.

11.Geometry and unitarity of scalar fields coupled to gravity

Authors:Minxi He, Kohei Kamada, Kyohei Mukaida

Abstract: We formulate scalar field theories coupled non-conformally to gravity in a manifestly frame-independent fashion. Physical quantities such as the $S$-matrix should be invariant under field redefinitions, and hence are represented by the geometry of the target space. This elegant geometric formulation, however, is obscured when considering the coupling to gravity because of the redundancy associated with the Weyl transformation. The well-known example is the Higgs inflation, where the target space of Higgs is flat in the Jordan frame but is curved in the Einstein frame. Furthermore, one can even show that any geometry of O$(N)$ nonlinear $\sigma$ models can be flattened by an appropriate Weyl transformation. In this letter, we extend the notion of the target space by including the conformal mode of the metric, and show that the extended geometry provides a compact formulation that is manifestly Weyl-transformation/field-redefinition invariant. We estimate the scale of the perturbative unitarity violation from the two-to-two scattering amplitudes based on this formalism.

12.Ratio of $J/Ψ$ and $Ψ(2s)$ exclusive photoproduction cross-sections as an indicator for the presence of non-linear QCD evolution

Authors:Marco Alcazar Peredo, Martin Hentschinski

Abstract: We investigate the proposal that the rise with energy of the ratio of the exclusive photo-production cross-sections of vector mesons $\Psi(2s)$ and $J/\Psi$ can serve as an indicator for the presence of high gluon densities and associated non-linear high energy evolution; we study this proposal for both photoproduction on a proton and a lead nucleus. While previous studies were based on unintegrated gluon distributions subject to linear (Balitsky-Fadin-Kuraev-Lipatov) and non-linear (Balitsky-Kovchegov) evolution equations, the current study is based on the Golec-Biernat W\"usthoff (GBW) and Bartels Golec-Biernat Kowalski (BGK) models, which allow assessing more directly the relevance of non-linear corrections for the description of the energy dependence of the photoproduction cross-section. We find that the rise of the ratio is directly related to the presence of a node in the $\Psi(2s)$ wave function and only manifests itself for the complete non-linear models, while it is absent for their linearized versions. We further provide predictions based on leading order collinear factorization and examine to which extent such an approach can mimic a ratio rising with energy. We also provide a description of recent ALICE data on the energy dependence of the photonuclear $J/\Psi$ production cross-section and give predictions for the energy dependence of the ratio of $\Psi(2s)$ and $J/\Psi$ photoproduction cross-sections for both scattering on a proton and a lead nucleus.

1.Quantum Corrections to Higgs Inflation in Einstein-Cartan Gravity

Authors:Minxi He, Kohei Kamada, Kyohei Mukaida

Abstract: This paper studies the quantum corrections to the Higgs inflation model in the context of the Einstein-Cartan (E-C) gravity in the large-$ N $ limit with $N$ being the number of real scalar components in Higgs. Recently, it is realized that the Higgs inflation in the E-C formalism smoothly connects those in the metric and the Palatini formalisms in the presence of a non-minimal coupling between the Higgs fields and the Nieh-Yan term. This motivates us to investigate the quantum corrections to the E-C Higgs inflation and to clarify how the Ricci curvature squared $ R^2 $ induced by the quantum corrections succeeds in Ultraviolet (UV)-extending the Higgs inflation in metric formalism while it fails in the Palatini case. We show that a generalized $ R^2 $-term required for the renormalization in the E-C formalism induces a new scalar degree of freedom (DoF), the scalaron, which gradually decouples with the system due to its increasing mass as approaching the Palatini limit. The presence of the scalaron extends the UV cutoff at vacuum of the original model except for the parameter space close to the Palatini limit. This UV-extension is expected to solve the strong coupling problem that may exist during (p)reheating in the absence of the scalaron.

2.Freeze-in bino dark matter in high scale supersymmetry

Authors:Chengcheng Han, Peiwen Wu, Jin Min Yang, Mengchao Zhang

Abstract: We explore a scenario of high scale supersymmetry where all supersymmetric particles except gauginos stay at a high energy scale $M_{\rm SUSY}$ which is much larger than the reheating temperature $T_\text{RH}$. The dark matter is dominated by bino component with mass around the electroweak scale and the observed relic abundance is mainly generated by the freeze-in process during the early universe. Considering the various constraints, we identify two available scenarios in which the supersymmetric sector at an energy scale below $T_\text{RH}$ consists of: a) bino; b) bino and wino. Typically, for a bino mass around 0.1-1 TeV and a wino mass around 2 TeV, we find that $M_{\rm SUSY}$ should be around $10^{12-14}$ GeV with $T_\text{RH}$ around $10^{4-6}$ GeV.

3.The Inverted Pendulum as a Classical Analog of the EFT Paradigm

Authors:Martin Beneke, Matthias König, Martin Link

Abstract: The inverted pendulum is a mechanical system with a rapidly oscillating pivot point. Using techniques similar in spirit to the methodology of effective field theories, we derive an effective Lagrangian that allows for the systematic computation of corrections to the so-called Kapitza equation. The derivation of the effective potential of the system requires non-trivial matching conditions, which need to be determined order by order in the power-counting of the problem. The convergence behavior of the series is investigated on the basis of high-order results obtained by this method.

4.New properties of elastic $pp$ and $p\bar{p}$ scattering at high energies

Authors:O. V. Selyugin

Abstract: Data-driving determination of the new properties of elastic scattering at small angles on the basis on all existing experimental data for $d\sigma/dt$ of $pp$ and $p\bar{p}$ at $\sqrt{s} \geq 540$ GeV allows us to obtain the main characteristics of the nonstandard terms of the elastic scattering amplitude. It was shown that the oscillation term has a different sign for $pp$ and $p\bar{p}$ reactions; hence, it is part of the Odderon amplitude. The energy dependence of the oscillation term and the term with an extremely large slope is determined. The period of the oscillation term agrees with the scaling properties predicted by the Auberson - Kinoshita - Martin (AKM) theorem. The high quality quantitative description of all data at $\sqrt{s} \geq 540$ GeV in the framework of the HEGS model supports such a phenomenon which can be connected with peripheral hadron interaction.

5.Probing chiral and flavored $Z^\prime$ from cosmic bursts through neutrino interactions

Authors:ShivaSankar K. A., Arindam Das, Gaetano Lambiase, Takaaki Nomura, Yuta Orikasa

Abstract: The origin of tiny neutrino mass is an unsolved puzzle leading to a variety of phenomenological aspects beyond the Standard Model (BSM). Among several interesting attempts, $U(1)$ gauge extension of Standard Model (SM) is a simple and interesting set-up where the so-called seesaw mechanism is incarnated by the addition of three generations of right-handed neutrinos followed by the breaking of $U(1)$ and electroweak symmetries. Such scenarios are anomaly free in nature appearing with a neutral BSM gauge boson ($Z^\prime$). In addition to that, there comes another open question regarding the existence of a non-luminous, hitherto unidentified object called Dark Matter (DM) originating from the measurement of its relic density. To explore properties of $Z^\prime$, we focus on chiral and flavored scenarios where $Z^\prime-$neutrinos interaction could be probed in the context of cosmic explosions like gamma-ray burst (GRB221009A, so far the highest energy), blazar (TXS 0506+056) and Active galaxy (NGC1068) respectively. The neutrino antineutrino annihilation produces electron-positron pair which could energize GRB through energy deposition. Taking the highest energy GRB under consideration and estimating the energy deposition rates we constrain $Z^\prime$ mass $(M_{Z^\prime})$ and the additional $U(1)$ coupling $(g_X)$ for chiral and flavored scenarios in the Schwarzchild, Hartle-Thorne and modified gravity frameworks. On the other hand, adding viable and alternative DM candidates in these models we study neutrino-DM scattering mediated by $Z^\prime$ in the $t-$ channel and estimate constraints on $g_X-M_{Z^\prime}$ plane using observed data of high energy neutrinos from cosmic blazar and active galaxy at the IceCube experiment. We compare our results with bounds obtained from different scattering, beam-dump and $g-2$ experiments.

6.Neutrino amplitude decomposition, $S$ matrix rephasing invariance, and reparametrization symmetry

Authors:Hisakazu Minakata

Abstract: The $S$ matrix rephasing invariance is one of the fundamental principles of quantum mechanics that originates in its probabilistic interpretation. For a given $S$ matrix which describes neutrino oscillation, one can define the two different rephased amplitudes $S_{\alpha \beta}^{ \text{Reph-1} } \equiv e^{ i (\lambda_{1} / 2E) x} S_{\alpha \beta}$ and $S_{\alpha \beta}^{ \text{Reph-2} } \equiv e^{ i (\lambda_{2} / 2E) x} S_{\alpha \beta}$, which are physically equivalent to each other, where $\lambda_{k} / 2E$ denotes the energy eigenvalue of the $k$-th mass eigenstate. The leading-order terms in $S_{\alpha \beta}^{ \text{Reph-1} }$ and $S_{\alpha \beta}^{ \text{Reph-2} }$ describe, respectively, the 1-3 and 2-3 level crossings around the atmospheric-scale resonance. We point out that the transformation of the reparametrization (Rep) symmetry obtained with ``Symmetry Finder'' maps $S_{\alpha \beta}^{ \text{Reph-1} }$ to $S_{\alpha \beta}^{ \text{Reph-2} }$, and vice versa, providing a local and manifest realization of the $S$ matrix rephasing invariance by the Rep symmetry. It strongly suggests a quantum mechanical nature of the Rep symmetry. An all-order treatment of the intimate relationships between the Rep symmetry and $S$ matrix rephasing invariance is attempted.

7.Predicting $\sin(2φ-φ_{s})$ azimuthal asymmetry in pion-proton induced Drell-Yan process using holographic light-front QCD

Authors:Bheemsehan Gurjar, Chandan Mondal

Abstract: We compute the $\sin(2\phi-\phi_{s})$ azimuthal asymmetry in the pion-nucleon induced Drell-Yan process within transverse momentum dependent factorization. We employ the holographic light-front pion wave functions to calculate its leading-twist transverse momentum dependent parton distributions (TMDs). The Boer-Mulders TMD of the pion is then convoluted with the transversity TMD of the proton evaluated in a light-front quark-diquark model constructed with the wave functions predicted by the soft-wall AdS/QCD to obtain the azimuthal asymmetry in the Drell-Yan process. The gluon rescattering is pivotal to predict nonzero pion Boer-Mulders TMD. We investigate the utility of a nonperturbative SU$(3)$ gluon rescattering kernel going beyond the usual approximation of perturbative U$(1)$ gluons. The holographic light-front QCD approach provides a powerful tool for exploring the role of nonperturbative QCD effects in the Drell-Yan process and may help to guide future experimental measurements.

8.Heavy quark diffusion and radiation at intermediate momentum

Authors:Juhee Hong

Abstract: We discuss heavy quark diffusion and radiation in an intermediate-momentum regime where finite mass effects can be significant. Diffusion processes are described in the Fokker-Planck approximation for soft momentum transfer, while radiative ones are taken into account by nearly collinear gluon emission from a single scattering in the Boltzmann equation. We also consider radiative corrections to the transverse momentum diffusion coefficient, which are $\mathcal{O}(g^2)$ suppressed than the leading-order diffusion coefficient but logarithmically enhanced. Numerical results show that the heavy quark distribution function depends on the energy loss mechanism so that the momentum dependence of suppression is distinguishable. Employing the heavy quark diffusion coefficient constrained by lattice QCD data, we estimate the nuclear modification factor which exhibits a transition from diffusion at low momentum to radiation at high momentum. The significance of radiative effects at intermediate momentum depends on the diffusion coefficient and running coupling constant.

9.Production of the heavy-flavour decay lepton in high-energy nuclear collisions

Authors:Sa Wang, Yao Li, Shuwan Shen, Ben-Wei Zhang, Enke Wang

Abstract: This paper presents a theoretical study on the production of the heavy-flavour decay lepton (HFL) in high-energy nuclear collisions at the LHC. The pp-baseline is calculated by the FONLL program, which matches the next-to-leading order pQCD calculation with the next-to-leading-log large-$p_T$ resummation. The in-medium propagation of heavy quarks is driven by the modified Langevin equations, which consider both the elastic and inelastic partonic interactions. We propose a method to separate the respective influence of the five factors, such as pp-spectra, the cold nuclear matter (CNM) effects, in-medium energy loss (E-loss), fragmentation functions (FFs), and decay channels, which may contribute to the larger $R_{AA}$ of HFL $\leftarrow b$ compared to that of HFL $\leftarrow c$ in nucleus-nucleus collisions. Based on quantitative analysis, we demonstrate that different decay channels of charm- and bottom-hadrons play an important role at $p_T<$5 GeV, while the mass-dependent E-loss dominates the higher $p_T$ region. It is also found that the influences of the CNM effects and FFs are insignificant, while different initial pp-spectra of charm and bottom quarks have a considerable impact at $p_T>$ 3 GeV. Furthermore, we explore the path-length dependence of jet quenching by comparing the HFL $R_{AA}$ in two different collision systems. Our investigations show smaller HFL $R_{AA}$ in Pb+Pb than that in Xe+Xe within the same centrality bin, which is consistent with the ALICE data. The longer propagation time and more effective energy loss of heavy quarks in Pb+Pb collisions play critical roles in the stronger yield suppression of the HFL compared to that in Xe+Xe. In addition, we observe a scaling behaviour of the HFL $R_{AA}$ in Xe+Xe and Pb+Pb collisions.

10.Indirect detection of dark matter with (pseudo)-scalar interactions

Authors:Simone Biondini, Julian Bollig, Stefan Vogl

Abstract: Indirect detection is one of the most powerful methods to search for annihilating dark matter. In this work, we investigate the impact of non-perturbative effects in the indirect detection of dark matter. For this purpose we utilize a minimal model consisting of a fermionic dark matter candidate in the TeV mass range that interacts via scalar- and pseudo-scalar interactions with a massive scalar mediator mixing with the Higgs. The scalar interaction induces an attractive Yukawa potential between dark matter particles, such that annihilations are Sommerfeld enhanced, and bound states can form. These non-perturbative effects are systematically dealt with (potential) non-relativistic effective field theories and we derive the relevant cross sections for dark matter. We discuss their impact on the relic density and indirect detection. Annihilations in dwarf galaxies and the Galactic Center require special care and we derive generalized $J$-factors for these objects that account for the non-trivial velocity dependence of the cross sections in our model. We use limits on the gamma-ray flux based on Fermi-LAT observations and limits on the rate of exotic energy injection from Planck to derive bounds on the parameter space of the model. Finally, we estimate the impact that future limits from the Cherenkov Telescope Array are expected to have on the model.

11.Positivity Bounds on Higgs-Portal Freeze-in Dark Matter

Authors:Seong-Sik Kim, Hyun Min Lee, Kimiko Yamashita

Abstract: We consider the relic density and positivity bounds for freeze-in scalar dark matter with general Higgs-portal interactions up to dimension-8 operators. When dimension-4 and dimension-6 Higgs-portal interactions are proportional to mass squares for Higgs or scalar dark matter in certain microscopic models such as massive graviton, radion or general metric couplings with conformal and disconformal modes, we can take the dimension-8 derivative Higgs-portal interactions to be dominant for determining the relic density via the 2-to-2 thermal scattering of the Higgs fields after reheating. We show that there is a wide parameter space for explaining the correct relic density from the freeze-in mechanism and the positivity bounds can curb out the dimension-8 derivative Higgs-portal interactions nontrivially in the presence of the similar dimension-8 self-interactions for Higgs and dark matter.

12.Muon $g-2$ and dark matter in Supersymmetric $SU(4)_c \times SU(2)_L \times SU(2)_R$

Authors:Qaisar Shafi, Amit Tiwari, Cem Salih Un

Abstract: The latest FermiLab muon $g-2$ result shows a $5\sigma$ discrepancy with a ``widely advertised" Standard Model prediction. We consider a supersymmetric $SU(4)_c \times SU(2)_L \times SU(2)_R$ model in which this discrepancy is resolved by including contributions to muon $g-2$ from a relatively light SUSY sector. A variety of realistic coannihilation scenarios can reproduce the observed dark matter relic abundance. With a significantly reduced discrepancy, of order $1 \sigma$ or less, the Higgsino-like dark matter solutions are also viable. We provide benchmark points for these solutions that will be probed in the direct detection dark matter experiments and collider searches.

13.Hadronic structure on the light-front IX . Orbital-spin-isospin wave functions of baryons

Authors:Nicholas Miesch, Edward Shuryak, Ismail Zahed

Abstract: This paper which is part of a series, is devoted to several technical issues. In the first part of the paper, we discuss the usual wavefunctions in the CM frame for baryons, by clarifying the representations of the three-quark permutation group $S_3$. We extend the analysis for up to five ``spinors" with $\rho,\lambda$-symmetry, and derive explicitly the totally symmetric wavefunctions modulo color. They are explicitly used to describe the excited nucleons $N^*$ states, in the P- and D-shell. We also show how to use symbolic operations in Mathematica, in spin-tensor notations to make explicit these states. For the S- and P-shells, the totally antisymmetric wavefunctions are given, and the pertinent matrix elements for the spin-dependent operators calculated, including the mixing between states with different total spin $S$. In the second part of the paper we turn to the light front wavefunctions, with an emphasis on the longitudinal wavefunctions, with a novel basis set. We also discuss their symmetries under permutations, and select the proper combinations for the transverse and longitudinal excitations for $N^*$ on the light front.

14.Tensor reduction of loop integrals

Authors:Charalampos Anastasiou, Julia Karlen, Matilde Vicini

Abstract: The computational cost associated with reducing tensor integrals to scalar integrals using the Passarino-Veltman method is dominated by the diagonalisation of large systems of equations. These systems of equations are sized according to the number of independent tensor elements that can be constructed using the metric and external momenta. In this article, we present a closed-form solution of this diagonalisation problem in arbitrary tensor integrals. We employ a basis of tensors whose building blocks are the external momentum vectors and a metric tensor transverse to the space of external momenta. The scalar integral coefficients of the basis tensors are obtained by mapping the basis elements to the elements of an orthogonaldual basis. This mapping is succinctly expressed through a formula that resembles the ordering of operators in Wick's theorem. Finally, we provide examples demonstrating the application of our tensor reduction formula to Feynman diagrams in QCD $2 \to 2$ scattering processes, specifically up to three loops.

15.Azimuthal Anisotropy at high transverse momentum in $p$-$p$ and $p$-$A$ collisions

Authors:Ismail Soudi, Abhijit Majumder

Abstract: We explore the possibility that the initial transverse momentum distribution of unpolarized and polarized partons within unpolarized protons, both with and without the anisotropy of unpolarized hadrons produced in the fragmentation of outgoing partons, could lead to the observed azimuthal anisotropy of high transverse momentum (high-$p_T$) hadrons produced in high energy proton-proton ($p$-$p$) or proton-ion ($p$-$A$) collisions. Including simple Gaussian forms for transverse momentum dependent parton distribution functions (PDF) and fragmentation functions, and assuming an $A^{1/3}$ enhancement of a PDF in $p$-$Pb$ collisions, we show that the observed anisotropy, with \emph{no modification} to the angle integrated spectra ($R_{pA}\!=1$) for 5 GeV $\lesssim p_T\lesssim 50$ GeV, can be straightforwardly understood as arising from a few processes dominated by gluon-gluon to gluon-gluon scattering.

1.Halo-independent bounds on Inelastic Dark Matter

Authors:Sunghyun Kang CQUeST and Sogang U., Arpan Kar CQUeST and Sogang U., Stefano Scopel CQUeST and Sogang U.

Abstract: We discuss halo-independent constraints on the Inelastic Dark Matter scenario, in which a Weakly Interaction Massive Particle (WIMP) state $\chi$ with mass $m_\chi$ interacts with nuclear targets by upscattering to a heavier state $\chi^{\prime}$ with mass $m_\chi+\delta$. In order to do so we adopt the single-stream method, that exploits the complementarity of Direct Detection (DD) and Capture in the Sun to extend the experimental sensitivity to the full range of incoming WIMP speeds. We show that a non-vanishing mass splitting $\delta$ modifies such range, and that for particular combinations of $m_\chi$ and $\delta$ the complementarity between the two detection techniques required by the method is lost. Specifically, assuming for the escape velocity in our Galaxy $u_{esc}$ the reference value $u_{esc}^{ref}$ = 560 km/s a halo-independent bound is possible when $\delta\lesssim$ 510 keV for a Spin-Independent interaction and when $\delta\lesssim$ 245 keV for a Spin-Dependent interaction (with the Spin-Independent value slightly reduced to $\delta\lesssim$ 490 keV when $u_{esc}>u_{esc}^{ref}$). We find that in the low-mass regime the bound from capture in the Sun is always more constraining than that for DD and is sufficient alone to provide a halo-independent constraint, while for large WIMP masses the halo-independent bound is given by a combination of capture in the Sun and DD. In this latter case, while for increasing values of $\delta$ the sensitivity range of initial speeds of the WIMP is reduced for both DD and capture in the Sun, such effect is more pronounced for DD than for capture. We also find that, for $u_{esc}$ = $u_{esc}^{ref}$, unless the mass of the target used in DD is larger than about four times that of the target driving capture in the Sun, DD does not play any role in the determination of the maximal value of $\delta$ for which a halo-independent bound is possible.

2.Robust features of QCD phase diagram through a Contact Interaction model for quarks: A view from the effective potential

Authors:Aftab Ahmad, Muhammad Azher, Alfredo Raya

Abstract: Our research delves into the QCD phase diagram in the temperature $T$ and quark chemical potential $\mu$ plane. We use a unique confining contact interaction effective model of quark dynamics that maintains the QCD symmetry intact. By embedding the model into a Schwinger-Dyson equations framework, within a Landau gauge rainbow-ladder-like truncation, we derive the gap equation. In order to accurately regulate the said equation, we utilize the Schwinger optimal time regularization scheme. We further derive the effective potential of the model by integrating the gap equation over the dynamical mass, which along with the confining length scale serve as parameters for the chiral and confinement deconfinement phase transitions, respectively. A cross-over transition is observed at low $\mu$ and above a critical value of the temperature $T_c$, whilst a first order phase transition is found for low $T$ at high density. The critical end point is estimated to be located at $(\mu_{E}/T_{c,0}=1.6, T_{E}/T_{c,0}=0.42)$, which falls within the range of other QCD effective models predictions. $T_{c,0} =208$ MeV is the critical temperature at vanishing $\mu$. Screening effects of the medium which dilute the strength of the effective coupling are considered by including the vacuum polarization contribution due to quarks at high temperatures into the framework. It locates the critical end point at $( \mu^{E}_{c}/T_c \approx2.6, T^{E}_{c}/T_c \approx 0.57)$, which hints for a deeper analysis of screening effects on models of this kind.

3.Neutrino mass model based on $Δ(27)$ symmetry and its implications

Authors:Ph. Wilina, N. Nimai Singh

Abstract: Implication of neutrino mass model based on $\Delta$(27) discrete flavor symmetry, on parameters of neutrino oscillations, CP violation and effective neutrino masses is studied using type-I seesaw mechanism. The Standard Model particle content is extended by adding two additional Higgs doublets, three right-handed neutrinos and two scalar triplets under $\Delta$(27) symmetry predicting diagonal charged lepton mass matrix. This can generate the desired deviation from $\mu - \tau$ symmetry. The resulting neutrino oscillation parameters are well agreed with the latest global fit oscillation data. The sum of the three absolute neutrino mass eigenvalues, $\sum\limits_{i}|m_{i}|$ (i=1,2,3) is found to be consistent with that of the value given by latest Planck cosmological data, $\sum\limits_{i}|m_{i}|<$0.12 eV. The model further predicts effective neutrino masses for neutrinoless double beta decay, 3.9 meV $\leq m_{ee}\leq$ 30.7 meV, tritium beta decay, 8.7 meV $\leq m_{\beta}\leq$ 30.6 meV, Jarlskog invariant, $J_{CP}=\pm 0.02196$ for CP violation, baryon asymmetry $Y_{B}=8.95\times 10^{-10}$ for normal hierarchical case and also 49.5 meV $\leq m_{ee}\leq$ 51.7 meV, 49.48 meV $\leq m_{\beta}\leq$ 51.4 meV, $J_{CP}=\pm 0.02191$, $Y_{B}=1.28\times 10^{-7}$ for inverted hierarchical case respectively.

4.Gravitational waves from metastable cosmic strings in Pati-Salam model in light of new pulsar timing array data

Authors:Waqas Ahmed, Talal Ahmed Chowdhury, Salah Nasri, Shaikh Saad

Abstract: A series of pulsar timing arrays (PTAs) recently observed gravitational waves at the nanohertz frequencies. Motivated by this remarkable result, we present a novel class of Pati-Salam models that give rise to a network of metastable cosmic strings, offering a plausible explanation for the observed PTA data. Besides, we introduce a hybrid inflationary scenario to eliminate magnetic monopoles that arise during the spontaneous symmetry breaking of the Pati-Salam gauge group to the Standard Model. The resulting scalar spectral index is compatible with Planck data, and the tensor-to-scalar ratio is anticipated to be extremely small. Moreover, we incorporate a non-thermal leptogenesis to generate the required baryon asymmetry in our framework. Finally, the gravitational wave spectra generated by the metastable cosmic strings not only correspond to signals observed in recent PTAs, including NANOGrav, but are also within the exploration capacity of both present and future ground-based and space-based experiments.

5.UV finite GUT with SUSY Breaking

Authors:Borut Bajc, Manuel Del Piano, Francesco Sannino

Abstract: We provide an example of an ultraviolet finite supersymmetric grand unified theory of safe rather than free nature endowed with a supersymmetric dynamical breaking mechanism. Our results simultaneously enlarge the number of ultraviolet consistent supersymmetric grand unified theories while providing a relevant example of how to achieve a consistent ultraviolet safe extension of the Standard Model enjoying the benefits of grand unified theories.

6.Flavor physics in SU(5) GUT with a 45 scalar representation

Authors:Toru Goto, Satoshi Mishima, Tetsuo Shindou

Abstract: We study a realistic SU(5) grand unified model, where a 45 representation of scalar fields is added to the Georgi-Glashow model in order to realize the gauge coupling unification and the masses and mixing of quarks and leptons. The gauge coupling unification together with constraints from proton decay implies mass splittings in scalar representations. We assume that an SU(2) triplet component of the 45 scalar, which is called $S_3$ leptoquark, has a TeV-scale mass, and color-sextet and color-octet ones have masses of the order of $10^6$ GeV. We calculate one-loop beta functions for Yukawa couplings in the model, and derive the low-energy values of the $S_3$ Yukawa couplings which are consistent with the grand unification. We provide predictions for lepton-flavor violation and lepton-flavor-universality violation induced by the $S_3$ leptoquark, and find that current and future experiments have a chance to find a footprint of our SU(5) model.

7.An Explicit Expression of Generation Function for One-Loop Tensor Reduction

Authors:Chang Hu, Tingfei Li, Jiyuan Shen, Yongqun Xu

Abstract: This work introduces an explicit expression for the generation function for the reduction of an $n$-gon to an $(n-k)$-gon. A novel recursive relation of generation function is formulated based on Feynman Parametrization in projective space, involving a single ordinary differential equation. The explicit formulation of generation functions provides crucial insights into the complex analytic structure inherent in loop amplitudes.

8.$B$ meson anomalies and large $B^{+}\to K^{+}ν\barν$ in non-universal $U(1)^\prime$ models

Authors:Peter Athron, R. Martinez, Cristian Sierra

Abstract: In view of both the latest LHCb measurement of $R_{K^{(*)}}$ and the newly $2.8\sigma$ deviation reported by Belle II on $B^{+}\to K^{+}\nu\bar{\nu}$ decays, we present a fit to the $B$ meson anomalies for various one and two dimensional hypothesis including complex Wilson coefficients. We show in a model-independent way that the generic non-universal $U(1)^{\prime}$ extensions of the SM, without flavour violation, fail to simultaneously fit those observables and corroborate that they can modify $\mathrm{BR}(B^{+}\to K^{+}\nu\bar{\nu})$ up to only a $10\%$. In view of this deficit, we propose a new way in which those models can accommodate the data at tree level by introducing lepton flavour violating couplings and non-diagonal elements of the charged lepton mixing matrix, with implications in future charged lepton flavour violation searches.

9.Reweighting Monte Carlo Predictions and Automated Fragmentation Variations in Pythia 8

Authors:Christan Bierlich, Philip Ilten, Tony Menzo, Stephen Mrenna, Manuel Szewc, Michael K. Wilkinson, Ahmed Youssef, Jure Zupan

Abstract: This work reports on a method for uncertainty estimation in simulated collider-event predictions. The method is based on a Monte Carlo-veto algorithm, and extends previous work on uncertainty estimates in parton showers by including uncertainty estimates for the Lund string-fragmentation model. This method is advantageous from the perspective of simulation costs: a single ensemble of generated events can be reinterpreted as though it was obtained using a different set of input parameters, where each event now is accompanied with a corresponding weight. This allows for a robust exploration of the uncertainties arising from the choice of input model parameters, without the need to rerun full simulation pipelines for each input parameter choice. Such explorations are important when determining the sensitivities of precision physics measurements. Accompanying code is available at

1.Sterile Neutrino Portal Dark Matter from Semi-Production

Authors:Ang Liu, Feng-Lan Shao, Zhi-Long Han, Yi Jin, Honglei Li

Abstract: In this paper, we study the feeble sterile neutrino portal dark matter under the $Z_3$ symmetry. The dark sector consists of one fermion singlet $\chi$ and one scalar singlet $\chi$, which transforms as $\chi\to e^{i2\pi/3}\chi, \phi\to e^{i2\pi/3}\phi$ under the $Z_3$ symmetry. Regarding fermion singlet $\chi$ as the dark matter candidate, the new interaction terms $y_\chi \phi \bar{\chi^c}\chi$ and $\mu\phi^3/2$ could induce various new production channels. For instance, when $m_\phi>2m_\chi$, the pair decay $\phi\to\chi\chi$ could be the dominant channel, rather than the delayed decay $\phi\to\chi\nu$. Another appealing scenario is when the dark sector is initially produced through the scattering process as $NN\to\chi\chi, NN\to\phi\phi,h\nu\to\chi\phi$, then the semi-production processes $N \chi\to\phi\phi, N\phi\to\phi\chi, N\chi\to\chi\chi$ could lead to the exponential growth of dark sector abundances. The phenomenology of sterile neutrino and the cosmological impact of the dark scalar are also considered in the $Z_3$ symmetric model.

2.Dark Mater Interactions From An Extra U(1) gauge symmetry with kinetic mixing and Higgs charge

Authors:Lianyou Shan, Zhao-Huan Yu

Abstract: We investigate fermionic dark matter interactions with standard model particles from an additional $\mathrm{U}(1)_\mathrm{X}$ gauge symmetry, assuming kinetic mixing between the $\mathrm{U}(1)_\mathrm{X}$ and $\mathrm{U}(1)_\mathrm{Y}$ gauge fields as well as a nonzero $\mathrm{U}(1)_\mathrm{X}$ charge of the Higgs doublet. For ensuring gauge-invariant Yukawa interactions and the cancellation of gauge anomalies, the standard model fermions are assigned $Y$-sequential $\mathrm{U}(1)_\mathrm{X}$ charges proportional to the Higgs charge. Although the Higgs charge should be small due to collider constraints, it is useful to decrease the effective cross section of dark matter scattering off nucleons by two orders of magnitude and easier evade from direct detection bounds. After some numerical scans performed in the parameter space, we find that the introduction of the Higgs charge can also enhance the dark matter relic density by at least two orders of magnitude. When the observed relic density and the direct detection constraints are tangled, at the case where the resonance effect is important for dark matter freeze-out, the Higgs charge can expand physical windows to some extent by relieving the tension between the relic density and the direct detection.

3.Gravitational Waves from Phase Transitions in Scale Invariant Models

Authors:Amine Ahriche, Shinya Kanemura, Masanori Tanaka

Abstract: We investigate the properties of the gravitational waves (GWs) generated during a strongly first order electroweak phase transition (EWPT) in models with the classical scale invariance (CSI). Here, we distinguish two parameter space regions that correspond to the cases of (1) light dilaton and (2) purely radiative Higgs mass (PRHM). In the CSI models, the dilaton mass, or the Higgs mass in the PRHM case, in addition to some triple scalar couplings are fully triggered by the radiative corrections (RCs). In order to probe the RCs effects on the EWPT strength and on the GW spectrum, we extend the standard model by a real singlet to assist the electroweak symmetry breaking and an additional scalar field $Q$ with multiplicity $N_Q$ and mass $m_Q$. After imposing all theoretical and experimental constraints, we show that a strongly first order EWPT with detectable GW spectra can be realized for the two cases of light dilaton and PRHM. We also show the corresponding values of the relative enhancement of the cross section for the di-Higgs production process, which is related to the triple Higgs boson coupling. We obtain the region in which the GW spectrum can be observed by different future experiments such as LISA and DECIGO. We also show that the scenarios (1) and (2) can be discriminated by future GW observations and measurements of the di-Higgs productions at future colliders.

4.Analysis of the strong decays of SU(3) partners of the $Ω(2012)$ baryon

Authors:T. M. Aliev, S. Bilmis, M. Savci

Abstract: We estimate the coupling constants and decay widths of the $SU(3)$ partners of the $\Omega(2012)$ hyperon, as discovered by the BELLE Collaboration, using the light cone sum rules method. Our study includes a comparison of the obtained results for relevant decay widths with those derived within the framework of the flavor $SU(3)$ analysis. We observe a good agreement between the predictions of both approaches. The results we obtain for the branching ratio can provide helpful insights for determining the nature of the $SU(3)$ partners of the $\Omega(2012)$ baryon.

5.Chiral perturbative reconstruction of the complex orthogonal matrix $R$ in Casas--Ibarra parameterization

Authors:Masaki J. S. Yang

Abstract: In this letter, we perform a chiral perturbative analysis by singular values $m_{Di}$ of the Dirac mass matrix $m_{D}$ for the type-I seesaw mechanism. In the basis where $m_{D} = V m_{D}^{\rm diag} U^{\dagger}$ is diagonal, the mass matrix of right-handed neutrinos $M_{R}$ is written by $M_{R} = m_{D}^{\rm diag} m^{-1} m_{D}^{\rm diag}$. If the mass matrix of light neutrinos $m$ has an inverse matrix and the singular values $m_{Di}$ are hierarchical ($m_{D1} \ll m_{D2} \ll m_{D3}$), the singular values $M_{i}$ and diagonalization matrix $U$ of $M_{R}$ are obtained perturbatively. By treating $m_{Di}$ and $V$ as input parameters, $m_{D}$ is represented in the basis where $M_{R}$ is diagonal, and we perturbatively derive the orthogonal matrix $R$ in Casas--Ibarra parameterization. As a result, $R$ is independent of $m_{Di}$ in the leading order, and it is reconstructed as an orthonormal basis $R_{i1} \simeq \pm \sqrt{m_{i} / m_{11} } (U_{\rm MNS}^{T} V^{*})_{i1} \, , R_{i2} \simeq \pm \epsilon_{ijk} R_{j3} R_{k1} \, , R_{i3} \simeq \pm {(U_{\rm MNS}^{\dagger} V)_{i3} / \sqrt {m_{i} (m^{-1})_{33}} } $. Here, $m_{i}$ is the masses of light neutrinos and $\pm$ denotes the independent degree of freedom for each column vector.

6.Searching for Heavy Leptophilic $Z'$: from Lepton Colliders to Gravitational Waves

Authors:Arnab Dasgupta, P. S. Bhupal Dev, Tao Han, Rojalin Padhan, Si Wang, Keping Xie

Abstract: We study the phenomenology of leptophilic $Z'$ gauge bosons at the future high-energy $e^+e^-$ or $\mu^+\mu^-$ colliders, as well as at the gravitational wave observatories. The leptophilic $Z'$ model, although well-motivated, remains largely unconstrained from current low-energy and collider searches for $Z'$ masses above ${\cal O}(100~{\rm GeV})$, thus providing a unique opportunity for future lepton colliders. Taking leptophilic $U(1)_{L_\alpha-L_\beta}~(\alpha,\beta=e,\mu,\tau)$ models as concrete examples, we show that future $e^+e^-$ and $\mu^+\mu^-$ colliders with multi-TeV center-of-mass energies provide unprecedented sensitivity to heavy $Z'$ bosons. Moreover, if these $U(1)$ models are classically scale-invariant, the phase transition at the $U(1)$ symmetry-breaking scale tends to be strongly first-order with ultra-supercooling, and leads to observable stochastic gravitational wave signatures. We find that the future sensitivity of gravitational wave observatories, such as advanced LIGO-VIRGO and Cosmic Explorer, can be complementary to the collider experiments, probing higher $Z'$ masses up to ${\cal O}(10^4~{\rm TeV})$.

7.Next-to-soft radiation from a different angle

Authors:Melissa van Beekveld, Abhinava Danish, Eric Laenen, Sourav Pal, Anurag Tripathi, Chris D. White

Abstract: Soft and collinear radiation in collider processes can be described in a universal way, that is independent of the underlying process. Recent years have seen a number of approaches for probing whether radiation beyond the leading soft approximation can also be systematically classified. In this paper, we study a formula that captures the leading next-to-soft QCD radiation affecting processes with both final- and initial-state partons, by shifting the momenta in the non-radiative squared amplitude. We first examine W+jet production, and show that a previously derived formula of this type indeed holds in the case in which massive colour singlet particles are present in the final state. Next, we develop a physical understanding of the momentum shifts, showing precisely how they disrupt the well-known angular ordering property of leading soft radiation.

8.Low Fine-Tuning with Heavy Higgsinos in Yukawa Unified SUSY GUTs

Authors:Cem Salih Un

Abstract: The work presented considers a class of minimally constructed Yukawa unified SUSY GUTs - NUHM2 - and explore their implications when their soft supersymmetry breaking Lagrangian is generalized by the non-holomorphic terms which provide extra contributions to the Higgsino mass and couple the supersymmetric scalar fields to the wrong Higgs doublets. With such a simple extension, it can be found several regions with interesting implications which cannot be realized in the usual restricted models. It is observed that the Yukawa unification solutions can be compatible with relatively light mass spectrum and acceptable low fine-tuning measurements. In the restricted models such effects can directly be addressed to the non-holomorphic terms. They can provide a slight improvement in the SM-like Higgs boson mass without altering the mass spectrum too much, and they can accommodate relatively lighter sbottom and stau masses, while they do not change the stop sector much. The dark matter can be Higgsino-like or Bino-like, but the experimental relic density measurements favor the Higgsino-like dark matter, while the Bino-like dark matter is predicted with a quite large relic density. Also several coannihilation scenarios are identified in the Higgsino-like dark matter regions, while the Bino-like dark matter do not allow any of such coannihilation processes. The presence of the non-holomorphic terms can weaken the impact from the phenomenological or indirect constraints such as low fine-tuning, Yukawa unification and rare decays of $B-$meson, the direct and model independent constraints still yield a strong strike on the solutions. Such constraints are discussed in regard of the current collider analyses on $\tau\tau$ events and direct detection of dark matter experiments.

1.Advances in the nested soft-collinear subtraction scheme

Authors:Chiara Signorile-Signorile, Davide Maria Tagliabue

Abstract: We discuss a path toward the generalisation of the nested soft-collinear subtraction scheme to arbitrary $2\rightarrow n$ processes. The scheme is designed to provide an efficient and process-independent procedure to extract and regulate infrared (IR) singularities arising from unresolved real radiation and combine them with explicit singularities in virtual corrections. The new approach is based on a reorganisation of the relevant subtraction terms into simple combinations of a relatively small number of recurring structures. This strategy leads to a drastic reduction in the computational effort required to derive integrated subtraction terms, while preserving the full generality of the scheme. We believe that this approach will allow for tackling the issue of regularising IR divergences at next-to-next-to-leading order in the strong coupling constant for arbitrary, multi-parton processes.

2.The Yukawa potential under weak magnetic field

Authors:Fabio L. Braghin, Marcelo Loewe, Cristian Villavicencio

Abstract: Weak magnetic field induced corrections for the Yukawa potential due to one pion exchange between two constituent quarks(nucleons) are presented. For that, the magnetic field effect on the pion propagator and on the pion form factor are taken into account. For that, an effective gluon propagator parameterized with an effective gluon mass ($M_g\sim 0.5$GeV) is considered. In the limit of magnetic field weak with respect to the constituent quark mass and pion mass, analytical and semi-analytical expressions can be obtained. Different types of contributions are found, isotropic or anisotropic, dependent on the pion mass and also on the constituent quark and effective gluon masses. Overall the corrections are of the order of $2\%$ to $5\%$ of the Yukawa potential at distances close to $2$fm, and they decrease slower than the Yukawa potential. The anistropic corrections are considerably smaller than the isotropic components. A sizable splitting between results due to magnetic field dependent neutral or charged pion mass is found.

3.QCD Axion Hybrid Inflation

Authors:Yuma Narita, Fuminobu Takahashi, Wen Yin

Abstract: When the inflaton is coupled to the gluon Chern-Simons term for successful reheating, mixing between the inflaton and the QCD axion is generally expected given the solution of the strong CP problem by the QCD axion. This is particularly natural if the inflaton is a different, heavier axion. We propose a scenario in which the QCD axion plays the role of the inflaton by mixing with heavy axions. In particular, if the energy scale of inflation is lower than the QCD scale, a hybrid inflation is realized where the QCD axion plays the role of the inflaton in early stages. We perform detailed numerical calculations to take account of the mixing effects. Interestingly, the initial misalignment angle of the QCD axion, which is usually a free parameter, is determined by the inflaton dynamics. It is found to be close to $\pi$ in simple models. This is the realization of the pi-shift inflation proposed in previous literature, and it shows that QCD axion dark matter and inflation can be closely related. The heavy axion may be probed by future accelerator experiments.

4.Three loop QCD corrections to the heavy-light form factors in the color-planar limit

Authors:Sudeepan Datta, Narayan Rana, V. Ravindran, Ratan Sarkar

Abstract: We present the analytic expressions for the color-planar contributions to the heavy-light form factors at three loops in perturbative QCD. These form factors play an important role in the precision predictions of various observables in top quark and flavour physics. We compute the master integrals using the method of differential equations. We perform the ultraviolet renormalization for all the appearing fields and parameters. The analytic results for the renormalized form factors are expressed in terms of generalized harmonic polylogarithms. We also study the Sudakov behaviour of these form factors in the asymptotic limit, which enables us to obtain the complete logarithmic three-loop and partial four-loop contributions.

5.As a consequence of H(650)->W+W-/ZZ, one predicts H++->W+W+ and H+->ZW+, as indicated by LHC data

Authors:Alain Le Yaouanc Université Paris-Saclay, CNRS/IN2P3, IJCLab, 91405 Orsay, France, François Richard Université Paris-Saclay, CNRS/IN2P3, IJCLab, 91405 Orsay, France

Abstract: Several indications for neutral scalars are observed at the LHC. One of them, a broad resonance peaked at about 650 GeV which we call H(650), was first observed by an outsider combining published histograms from ATLAS and CMS on ZZ ->4 leptons searches, and this combination shows a local significance close to 4 s.d. Since then, CMS has reported two other indications at the same mass, with similar local significances: H ->WW -> lepton nu lepton nu and H->bbh(125) where h(125) ->2 photons. ATLAS has completed its analysis of ZZ->4 leptons from which we infer an indication for H(650) with 3.5 s.d. significance. Assuming that the mass is already known from the former set, and combining these three results, one gets a global statistical significance above 6 s.d. H(650) has a coupling to WW similar to h(125) and therefore we argue that a sum rule (SR) required by unitarity for WW scattering implies that there should be a compensating effect from a doubly charged scalar H++, with a large coupling to W+W+. We therefore predict that this mode should become visible through the vector boson fusion process W+W+->H++, naturally provided by LHC. A recent indication for H++(450)->W+W+ from ATLAS allows a model independent interpretation of this result through the SR constraint which gives BR(H++->W+W+)=10%, implying the occurrence of additional decay modes H+W+ and H+H+ from one or several light H+ with masses below mH++ - mW or MH++/2, that is mH+ < 370 GeV or 225 GeV. A similar analysis is provided for H+(375)->ZW, indicated by ATLAS and CMS. Both channels suggest a scalar field content similar to the Georgi Machacek model with triplets, at variance with the models usually considered.

1.Quartic Gradient Flow

Authors:Muzi Hong, Ryusuke Jinno

Abstract: Saddle-point configurations, such as the Euclidean bounce and sphalerons, are known to be difficult to find numerically. In this Letter we study a new method, Quartic Gradient Flow, to search for such configurations. The central idea is to introduce a gradient-flow-like equation in such a way that all the fluctuations around the saddle-point have eigenvalues that are square of the eigenvalues of the original quadratic operator. We illustrate how the method works for the Euclidean bounce and sphalerons.

2.Kramers-Krönig approach to the electric permittivity of the vacuum in a strong constant electric field

Authors:Hidetoshi Taya, Charlie Ironside

Abstract: We study the electric permittivity of the QED vacuum in the presence of a strong constant electric field, motivated by the analogy between the dynamically-assisted Schwinger effect in strong-field QED and the Franz-Keldysh effect in semiconductor physics. We develop a linear-response theory based on the non-equilibrium in-in formalism and the Furry-picture perturbation theory, with which and also utilizing the Kramers-Kr\"onig relation, we calculate the electric permittivity without assuming weak fields and low-frequency probes. We discover that the electric permittivity exhibits characteristic oscillating dependence on the probe frequency, which directly reflects the change of the QED-vacuum structure by the strong field. We also establish a quantitative correspondence between the electric permittivity and the number of electron-positron pairs produced by the dynamically-assisted Schwinger effect.

3.Twist-3 Contributions in Semi-Inclusive DIS in the Target Fragmentation Region

Authors:K. B. Chen, J. P. Ma, X. B. Tong

Abstract: We present the complete results up to twist-3 for hadron production in the target fragmentation region of semi-inclusive deep inelastic scattering with a polarized lepton beam and polarized nucleon target. The non-perturbative effects are factorized into fracture functions. The calculation up to twist-3 is non-trivial since one has to keep gauge invariance. By applying collinear expansion, we show that the hadronic tensor can be expressed by gauge-invariant fracture functions. We also present the results for the structure functions and azimuthal asymmetries.

4.Supersymmetric hybrid inflation and metastable cosmic strings in $SU(4)_c \times SU(2)_L \times U(1)_R$

Authors:Adeela Afzal, Maria Mehmood, Mansoor Ur Rehman, Qaiser Shafi

Abstract: We construct a realistic supersymmetric model for superheavy metastable cosmic strings (CSs) that can be investigated in the current pulsar timing array (PTA) experiments. We consider shifted $\mu$ hybrid inflation in which the symmetry breaking $SU(4)_c \times SU(2)_L \times U(1)_R\rightarrow SU(3)_c\times SU(2)_L \times U(1)_{B-L}\times U(1)_R$ proceeds along an inflationary trajectory such that the topologically unstable primordial monopoles are inflated away. The breaking of $U(1)_{B-L} \times U(1)_R \rightarrow U(1)_Y$ after inflation ends yields the metastable CSs that generate the stochastic gravitational wave background (SGWB) which is consistent with the current PTA data set. The scalar spectral index $n_s$ and the tensor to scalar ratio $r$ are also compatible with Planck 2018. We briefly discuss both reheating and leptogenesis in this model.

5.Two-loop form factors for diphoton production in quark annihilation channel with heavy quark mass dependence

Authors:Matteo Becchetti, Roberto Bonciani, Leandro Cieri, Federico Coro, Federico Ripani

Abstract: We present the computation of the two-loop form factors for diphoton production in the quark annihilation channel. These quantities are relevant for the NNLO QCD corrections to diphoton production at LHC recently presented in arXiv:2308.10885. The computation is performed retaining full dependence on the mass of the heavy quark in the loops. The master integrals are evaluated by means of differential equations which are solved exploiting the generalised power series technique.

6.Relations Between Partition Functions of with Various Gauge Fields from Double Copy Relations in AdS/CFT Correspondence

Authors:Jia-rui Guo

Abstract: In this work, we use double copy relation to obtain AdS on-shell gravity coupling to tensor instead of scalar field, giving more complex structures, which leads to an relation between AdS on-shell gauge field and gauge field in CFT. This also provide a comparison from the strong-weak correspondence, which could be applied in matter with QCD and QED fields and their thermodynamics.

7.Supersymmetric $U(1)_{B-L}$ flat direction and NANOGrav 15 year data

Authors:Rinku Maji, Wan-Il Park

Abstract: We show that, when connected with monopoles, the \textit{flat} $D$-flat direction breaking the local $U(1)_{B-L}$ symmetry as an extension of the minimal supersymmetric standard model can be responsible for the signal of a stochastic gravitational wave background recently reported by NANOGrav collaborations, while naturally satisfying constraints at high frequency band. Thanks to the flatness of the direction, a phase of thermal inflation arises naturally. The reheating temperature is quite low, and suppresses signals at frequencies higher than the characteristic frequency set by the reheating temperature. Notably, forthcoming spaced-based experiments such as LISA can probe the cutoff frequency, providing an indirect clue of the scale of soft SUSY-breaking mass parameter.

8.Searching for neutrino-modulino oscillations at the Forward Physics Facility

Authors:Luis A. Anchordoqui, Ignatios Antoniadis, Karim Benakli, Jules Cunat, Dieter Lust

Abstract: We make use of swampland conjectures to explore the phenomenology of neutrino-modulino mixing in regions of the parameter space that are within the sensitivity of experiments at the CERN's Forward Physics Facility (FPF). We adopt the working assumption of Dirac mass terms which couple left- and right-handed neutrinos. We further assume that the 3 right-handed neutrinos are 0-modes of bulk 5-dimensional states in the dark dimension, a novel scenario which has a compact space with characteristic length-scale in the micron range that produces a natural suppression of the 4-dimensional Yukawa couplings, yielding naturally light Dirac neutrinos. We formulate a specific realization of models with high-scale supersymmetry breaking that can host a rather heavy gravitino ($m_{3/2} \sim 250$ TeV) and a modulino with mass scale ($m_4 \sim 50$ eV) within the FPF discovery reach.

9.Calculation of lepton magnetic moments in quantum electrodynamics: a justification of the flexible divergence elimination method

Authors:Sergey Volkov

Abstract: The flexible method of reduction to finite integrals, briefly described in earlier publications of the author, is described in detail. The method is suitable for the calculation of all quantum electrodynamical contributions to the magnetic moments of leptons. It includes mass-dependent contributions. The method removes all divergences (UV, IR and mixed) point-by-point in Feynman parametric space without any usage of limit-like regularizations. It yields a finite integral for each individual Feynman graph. The subtraction procedure is based on the use of linear operators applied to the Feynman amplitudes of UV-divergent subgraphs; a placement of all terms in the same Feynman parametric space is implied. The final result is simply the sum of the individual graph contributions; no residual renormalization is required. The method also allows us to split the total contribution into the contributions of small gauge-invariant classes. The procedure offers a great freedom in the choice of the linear operators. This freedom can be used for improving the computation speed and for a reliability check. The mechanism of divergence elimination is explained, as well as the equivalence of the method and the on-shell renormalization. For illustrative purposes, all 4-loop contributions to the anomalous magnetic moments of the electron and muon are given for each small gauge-invariant class, as well as their comparison with previously known results. This also includes the contributions that depend on the ratios of the tau-lepton mass to the electron and muon mass.

10.NNLO+PS $W^+W^-$ production using jet veto resummation at NNLL$'$

Authors:Alessandro Gavardi, Matthew A. Lim, Simone Alioli, Frank Tackmann

Abstract: We construct a novel event generator for the process $p \> p \to \ell^- \> \bar{\nu}_\ell \> \ell'^+ \> \nu_{\ell'}$, which matches fixed-order predictions at next-to-next-to-leading order in the strong coupling to a parton shower program. The matching is achieved using the GENEVA method, in this case exploiting a resummed calculation for the hardest jet transverse momentum at next-to-next-to-leading logarithmic accuracy obtained via soft-collinear effective theory and implemented in the C++ library SCETlib. This choice of resolution variable ensures that the introduction of a jet veto, commonly used by experimental analyses to reject multi-jet background events, does not result in the appearance of unmitigated large logarithms for low veto scales before showering. After validating our partonic results against publicly available fixed order and resummed calculations, we compare our predictions to measurements taken at the ATLAS and CMS experiments, finding good agreement. This is the first NNLO+PS accurate event generator to use the hardest jet transverse momentum as a resolution variable.

11.Flavor physics beyond the Standard Model and the Kobayashi-Maskawa legacy

Authors:Gino Isidori

Abstract: The Kobayashi-Maskawa (KM) hypothesis about the existence of a third generation of quarks represents a cornerstone of the Standard Model (SM). Fifty years after this seminal paper, flavor physics continues to represent a privileged observatory on physics occurring at high energy scales. In this paper I first review this statement using general effective-theory arguments, highlighting some interesting modern lessons from the KM paper. I then discuss some novel extensions of the SM based on the concept of flavor deconstruction: the hypothesis that gauge interactions are manifestly flavor non universal in the ultraviolet. The phenomenological consequences of this class of models are also briefly illustrated.

1.Modeling Backward-Angle ($u$-channel) Virtual Compton Scattering at an Electron-Ion Collider

Authors:Zachary Sweger, Spencer R. Klein, Yuanjing Ji, Minjung Kim, Saeahram Yoo, Ziyuan Zeng, Daniel Cebra, Xin Dong

Abstract: High-energy backward ($u$-channel) reactions can involve very large momentum transfers to the target baryons, shifting them by many units of rapidity. These reactions are difficult to understand in conventional models in which baryon number is carried by the valence quarks. Backward Compton scattering is an especially attractive experimental target, because of its simple final state. There is currently limited data on this process, and that data is at low center-of-mass energies. In this paper, we examine the prospects for studying backward Compton scattering at the future Electron-Ion Collider (EIC). We model the cross-section and kinematics using the limited data on backward Compton scattering and backward meson production, and then simulate Compton scattering at EIC energies, in a simple model of the ePIC detector. Generally, the proton is scattered toward mid-rapidity, while the produced photon is in the far-forward region, visible in a Zero Degree Calorimeter (ZDC). We show that the background from backward $\pi^0$ production can be rejected using a high-resolution, well-segmented ZDC.

2.Persistent homology of collider observations: when (w)hole matters

Authors:Jyotiranjan Beuria

Abstract: Topological invariants have played a fundamental role in the advancement of theoretical high energy physics. Physicists have used several kinematic techniques to distinguish new physics predictions from the Standard Model (SM) of particle physics at Large Hadron Collider (LHC). However, the study of global topological invariants of the collider signals has not yet attracted much attention. In this article, we present, a novel approach to study collider signals using persistent homology. The global topological properties of the ensemble of events as expressed by measures like persistent entropy, Betti area, etc. are worth considering in addition to the traditional approach of using kinematic variables event by event. In this exploratory study, we first explore the characteristic topological signature of a few SM electroweak resonant productions. Next, we use the framework to distinguish global properties of the invisible Higgs decay processes in the SM and a real singlet extension of the SM featuring stable singlet scalar dark matter.

3.Cooper-Frye spectra of hadrons with viscous corrections including feed down from resonance decays

Authors:Andreas Kirchner, Eduardo Grossi, Stefan Floerchinger

Abstract: A method to calculate hadron momentum spectra after feed down from resonance decays in the context of ultra-relativistic heavy ion collisions described by relativistic fluid dynamics is presented. The conceptual setup uses the Cooper-Frye freeze-out integration together with an integral operator describing resonance decays. We provide explicit expressions for the integration over the freeze-out surface for a smooth and symmetric background solution, as well as for linearized perturbations around it. A major advantage of our method is that many integrals can be precomputed independently of a concrete hydrodynamic simulation. Additionally, we examine the influence of adding heavier resonances to the decay chain on the spectrum of pions and show how to include a phase with partial chemical equilibrium in order to separate the chemical from the kinetic freeze-out.

4.Logarithmic divergent friction on ultrarelativistic bubble walls

Authors:Wen-Yuan Ai

Abstract: We calculate the friction experienced by ultrarelativistic bubble walls resulting from the $1 \rightarrow 2$ light-to-heavy transition process, with finite-wall-width effects fully taken into account. In this process, the light particle is excited from the order-parameter scalar field, while the two heavy particles are excitations of a dark matter scalar field. Unlike earlier estimates suggesting a friction scaling as $\gamma_w^0$, where $\gamma_w$ represents the Lorentz factor of the wall velocity, our more precise numerical analysis reveals a logarithmic dependence of the friction on $\gamma_w$. We offer a numerical fit to capture this frictional pressure accurately. Our analysis verifies that the friction stemming from the $1 \rightarrow 2$ light-to-heavy transition is typically much smaller than the friction from the $1 \rightarrow 1$ transmission of the dark matter particles.

5.Diffractive Processes at Next-to-Leading Order in the Dipole Picture

Authors:Jani Penttala

Abstract: In this thesis, we calculate diffractive processes at next-to-leading order (NLO) in the high-energy limit, with an emphasis on exclusive vector meson production and inclusive diffraction in deep inelastic scattering (DIS). Calculations in the high-energy limit can be done using the dipole picture, the basics of which are briefly reviewed. This includes using the color-glass condensate effective field theory to describe the nonperturbative dipole-target scattering amplitude which appears in practically all calculations in the dipole picture. The universality of the dipole-target scattering amplitude at NLO is shown numerically, in the sense that the same dipole-target scattering amplitude can be used to describe the data in both massless and massive quark production in inclusive DIS, and also in diffractive processes where exclusive vector meson production is considered. The analytical NLO calculations of exclusive vector meson production and inclusive diffraction in DIS are also explained. Exclusive vector meson production is calculated in the nonrelativistic limit for heavy mesons and the limit of large photon virtuality for light mesons. Also, the importance of including relativistic corrections to the heavy vector meson wave function in exclusive vector meson production is considered. For inclusive diffraction in DIS, we focus on the NLO corrections to the final state and show how the divergences cancel.

6.A TMD-based model for Hadronization off heavy nuclei

Authors:Raphaël Dupré, Federico Ceccopieri

Abstract: Semi-inclusive deep inelastic scattering (SIDIS) off nuclei is a unique process to study the parton propagation mechanism and its modification induced by the presence of the nuclear medium. It allows us to probe the medium properties, particularly the cold nuclear matter transport coefficient, which can be directly linked to the nuclear gluon density. We present here a model for hadron production in deep inelastic lepton-nucleus scattering, which takes into account the hadronic transverse momentum of final state particles via transverse-momentum dependent (TMD) parton distributions and fragmentation functions. We implement parton energy loss and hadronic absorption with a geometrical model of the nucleus. The model is compared with the nuclear SIDIS multiplicity ratios and transverse-momentum broadening data from the CLAS, HERMES, and EMC collaborations, aiming for a simultaneous description of these data sets. We obtain a good agreement over the various nuclear targets and the wide kinematical range of those experiments. We best describe the data with a transport coefficient \hat q = 0.3 GeV/fm 2 , and we highlight the importance and the role of correlations in extracting this quantity.

7.Study of Scalar Non Standard Interaction at Protvino to Super-ORCA experiment

Authors:Dinesh Kumar Singha, Rudra Majhi, Lipsarani Panda, Monojit Ghosh, Rukmani Mohanta

Abstract: In this paper we have studied the phenomenon of non-standard interaction mediated by a scalar field (SNSI) in the context of P2SO experiment and compared its sensitivity with DUNE. In particular, we have studied the capability of these two experiments to put bounds on the diagonal SNSI parameters i.e., $\eta_{ee}$, $\eta_{\mu\mu}$ and $\eta_{\tau\tau}$ and studied the impact of these parameters on the determination of neutrino mass ordering, octant of $\theta_{23}$ and CP violation (CPV). In our analysis we find that, the parameter $\Delta m^2_{31}$ has a non-trivial role if one wants estimate the bounds on $\eta_{\mu\mu}$ and $\eta_{\tau\tau}$ assuming SNSI does not exist in nature. Our results show that sensitivity of P2SO and DUNE to constraint $\eta_{\mu\mu}$ and $\eta_{\tau\tau}$ are similar whereas the sensitivity of DUNE is slightly better for $\eta_{ee}$. We find that the mass ordering and CPV sensitivities are mostly affected by $\eta_{ee}$ compared to $\eta_{\mu \mu}$ and $\eta_{\tau \tau}$ if one assumes SNSI exists in nature. On the other hand, octant sensitivity is mostly affected by $\eta_{\mu \mu}$ and $\eta_{\tau \tau}$. These sensitivities can be either higher or lower than the standard three flavour scenario depending on the relative sign of the SNSI parameters. Regarding the precision of atmospheric mixing parameters, we find that the precision of $\theta_{23}$ deteriorates significantly in the presence of $\eta_{\mu\mu}$ and $\eta_{\tau\tau}$.

8.Initial-Final and Initial-Initial antenna functions for real radiation at next-to-leading order

Authors:Elliot Fox Durham U., IPPP, Nigel Glover Durham U., IPPP and Zurich U.

Abstract: The antenna subtraction method has achieved remarkable success in various processes relevant to the Large Hadron Collider. In Reference [1], an algorithm was proposed for constructing real-radiation antenna functions for electron-positron annihilation, directly from specified unresolved limits, accommodating any number of real emissions. Here, we extend this algorithm to build antennae involving partons in the initial state, specifically the initial-final and initial-initial antennae. Using this extended algorithm, we explicitly construct all NLO QCD antenna functions and compare them with previously extracted antenna functions derived from matrix elements. Additionally, we rigorously match the integration of the antenna functions over the initial-final and initial-initial unresolved phase space with the previous approach, providing an independent validation of our results. The improved antenna functions are more compact and reduced in number, making them more readily applicable for higher-order calculations.

9.Full top-quark mass dependence in diphoton production at NNLO in QCD

Authors:Matteo Becchetti, Roberto Bonciani, Leandro Cieri, Federico Coro, Federico Ripani

Abstract: In this paper we consider the diphoton production in hadronic collisions at the next-to-next-to-leading order (NNLO) in perturbative QCD, taking into account for the first time the full top quark mass dependence up to two loops (full NNLO). We show selected numerical distributions, highlighting the kinematic regions where the massive corrections are more significant. We make use of the recently computed two-loop massive amplitudes for diphoton production in the quark annihilation channel. The remaining massive contributions at NNLO are also considered, and we comment on the weight of the different types of contributions to the full and complete result.

1.Off-shellness in generalized parton distributions and form factors of the pion

Authors:Vanamali Shastry, Wojciech Broniowski, Enrique Ruiz Arriola

Abstract: We study the effects of off-shellness in the generalized parton distributions of the pion. On general grounds, these distributions exhibit a richer structure than in the on-shell case due to absence of the crossing symmetry. In particular, their moments involve additional terms odd in the skewness parameter, associated with new form factors. We bring up relations between the off-shell charge and gravitational form factors, as well as the pion form factor, and discuss their derivations based on the Ward-Takahashi identities. We illustrate the features at the (leading-$N_c$) one-quark-loop level with the help of the spectral quark model of the pion, constructed to embed the vector meson dominance. Simple analytic expressions for the form factors and the distributions follow. Thus obtained off-shell generalized parton distributions are evolved from the quark model scale to higher scales with the LO DGLAP equations. We evaluate the corresponding Compton amplitudes which enter the cross-section for the electroproduction of the pion off the proton (the Sullivan process). It is found in our model that the effects of off-shellness in the generalized parton distribution are substantial, however, they can be largely canceled by the corresponding off-shell corrections to the pion propagator. In particular, this is the case of the Compton form factors entering the deeply virtual Compton scattering amplitude. As a result, we expect small off-shellness effects in electroproduction reactions, such as the Sullivan process.

2.Color symmetry and confinement as an underlying superconformal structure in holographic QCD

Authors:Guy F. de Teramond, Stanley J. Brodsky

Abstract: Dedicated to the memory of our colleague, Harald Fritzsch, who, together with Murray Gell-Mann, introduced the color quantum number as the exact symmetry responsible for the strong interaction, thus establishing quantum chromodynamics (QCD) as a fundamental non-Abelian gauge theory. A basic understanding of hadron properties, however, such as confinement and the emergence of a mass scale, from first principles QCD has remained elusive: Hadronic characteristics are not explicit properties of the QCD Lagrangian and perturbative QCD, so successful in the large transverse momentum domain, is not applicable at large distances. In this article, we shall examine how this daunting obstacle is overcome in holographic QCD with the introduction of a superconformal symmetry in anti de Sitter (AdS) space which is responsible for confinement and the introduction of a mass scale within the superconformal group. When mapped to light-front coordinates in physical spacetime, this approach incorporates supersymmetric relations between the Regge trajectories of meson, baryon and tetraquark states which can be visualized in terms of specific $SU(3)_C$ color representations of quarks. We will also briefly discuss here the implications of holographic models for QCD color transparency in view of the present experimental interest. Invited contribution to the book dedicated to the memory of Harald Fritzsch.

3.Proton number cumulants in a modified van der Waals hadron resonance gas

Authors:Kshitish Kumar Pradhan, Ronald Scaria, Dushmanta Sahu, Raghunath Sahoo

Abstract: An estimate of the proton number cumulants in the hadronic matter is presented considering a van der Waals-type interaction between the constituent particles. We argue that the attractive and repulsive parameters in the VDW hadron resonance gas (VDWHRG) model change as functions of baryochemical potential ($\mu_{B}$) and temperature ($T$). This, in turn, affects the estimation of thermodynamic properties and, consequently, the conserved charge fluctuations. We employ a simple parametrization to bring in the center-of-mass energy ($\sqrt{s_{\rm NN}}$) dependence on temperature and baryochemical potential and then estimate the proton number cumulants with the modified approach. The modified van der Waals hadron resonance gas model (MVDWHRG) explains the existing experimental data very well.

4.$K^+ N$ elastic scatterings for estimation of in-medium quark condensate with strange quarks

Authors:Yutaro Iizawa, Daisuke Jido, Stephan Hübsch

Abstract: We revisit the low-energy $K^+N$ elastic scatterings in the context of the in-medium quark condensate with strange quarks. The chiral ward identity connects the in-medium quark condensate to the soft limit value of the pseudoscalar correlation function evaluated in nuclear matter. The in-medium correlation function of the psuedoscalar fields with strangeness describes in-medium kaon propagation and is obtained by kaon-nucleon scattering amplitudes in the low density approximation. We construct the kaon-nucleon scattering amplitudes in chiral perturbation theory up to the next-to-leading order and add some terms of the next-to-next-to-leading order with the strange quark mass to improve expansion of the strange quark sector. We also consider the effect of a possible broad resonance state around $P_\mathrm{lab} = 600$ MeV/c for $I=0$ reported in the previous study. The low energy constants are determined by existent $K^+N$ scattering data. We obtain good reproduction of the $K^+p$ scattering amplitude by chiral perturbation theory, while the description of the $KN$ amplitude with $I=0$ is not so satisfactory due to the lack of low energy data. Performing analytic continuation of the scattering amplitudes obtained by chiral perturbation theory to the soft limit, we estimate the in-medium strange quark condensate.

5.Deeply-virtual and photoproduction of mesons at higher-order and higher-twist

Authors:K. Passek-Kumericki

Abstract: Both deeply-virtual and photoproduction of mesons offer promising access to generalized parton distributions and complementary description of different kinematical regions. The higher-order contributions offer stabilizing effect with respect to the dependence on renormalization scales, while higher-twist effects have been identified as especially important in the case of the production of pseudo-scalar mesons. This was confirmed by recent evaluation of the complete twist-3 contribution to $\pi$ and $\eta$/$\eta'$ photoproduction and its confrontation with experimental data.

6.Two-loop radiative corrections to $e^+ e^-\rightarrow γγ^*$ cross section

Authors:V. S. Fadin, R. N. Lee

Abstract: The increasing accuracy of current and planned experiments to measure the anomalous magnetic moment of the muon requires more precision and reliability of its theoretical calculation. For this purpose, we calculate the differential cross section for the process of annihilation of an electron-positron pair into two photons, one of which is virtual, accompanied by the emission of soft photons, taking into account radiative corrections of the order $\alpha^2$. The results obtained can be used to improve the accuracy of calculating the contribution of the hadron vacuum polarization to the muon anomalous moment. It is shown that all logarithmically amplified two-loop corrections can be easily found using modern theorems of soft and collinear factorizations and available one-loop results.

7.Cabibbo angle anomalies and a global fit to vector-like quarks

Authors:Matthew Kirk

Abstract: The most recent determinations of $V_{ud}$ from superallowed beta decays lead to a discrepancy when compared to the value implied by mesonic CKM measurements combined with CKM unitarity. On top of this, improved precision in lattice QCD calculations have revealed another discrepancy between the $V_{us}$ determinations from kaon and pion semi-leptonic decays. The combination of these can be referred to as the Cabibbo angle anomaly, which we find has a significance of around $3\,\sigma$. After summarising the current state of these issues, I will talk about new physics models that modify semi-leptonic decays as potential explanations, and why vector-like quarks in particular appear the most promising candidates. I will then discuss the results of a global fit to various vector-like quark models, and how other constraints are important in determining the most likely explanation. Finally I will touch on future experiments that could shed further light on the situation.

8.A Hybrid Type I + III Inverse Seesaw Mechanism in $U(1)_{R-L}$-symmetric MSSM

Authors:Cem Murat Ayber, Seyda Ipek

Abstract: We show that, in a $U(1)_{R-L}$-symmetric supersymmetric model, the pseudo-Dirac bino and wino can give rise to three light neutrino masses through effective operators, generated at the messenger scale between a SUSY breaking hidden sector and the visible sector. The neutrino-bino/wino mixing follows a hybrid type I+III inverse seesaw pattern. The light neutrino masses are governed by the ratio of the $U(1)_{R-L}$-breaking gravitino mass, $m_{3/2}$, and the messenger scale $\Lambda_M$. The charged component of the $SU(2)_L$-triplet, here the lightest charginos, mix with the charged leptons and generate flavor-changing neutral currents at tree level. We find that resulting lepton flavor violating observables yield a lower bound on the messenger scale, $\Lambda_M \gtrsim (500-1000)~{\rm TeV}$ for a simplified hybrid mixing scenario. We identify interesting mixing structures for certain $U(1)_{R-L}$-breaking singlino/tripletino Majorana masses. For example, in some parameter regimes, bino or wino has no mixing with the electron neutrino. We also describe the rich collider phenomenology expected in this neutrino-mass generation mechanism.

9.A Survey of Neutrino Flavor Models and the Neutrinoless Double Beta Decay Funnel

Authors:Peter B. Denton, Julia Gehrlein

Abstract: The neutrinoless double beta decay experimental effort continues to make tremendous progress with hopes of covering the inverted neutrino mass hierarchy in coming years and pushing from the quasi-degenerate hierarchy into the normal hierarchy. As neutrino oscillation data is starting to suggest that the mass ordering may be normal, we may well be faced with staring down the funnel of death: a region of parameter space in the normal ordering where for a particular cancellation among the absolute neutrino mass scale, the Majorana phases, and the oscillation parameters, the neutrinoless double beta decay rate may be vanishingly small. To answer the question if this region of parameter space is theoretically preferred, we survey five broad categories of flavor models which make various different predictions for parameters relevant for neutrinoless double beta decay to determine how likely it is that the rate may be in this funnel region. We find that a non-negligible fraction of flavor models are at least partially in the funnel region. Our results can guide model builders and experimentalists alike in focusing their efforts on theoretically motivated regions of parameter space.

10.Pre-equilibrium photons from the early stages of heavy-ion collisions

Authors:Oscar Garcia-Montero, Aleksas Mazeliauskas, Philip Plaschke, Sören Schlichting

Abstract: We use QCD kinetic theory to compute photon production in the chemically equilibrating Quark-Gluon Plasma created in the early stages of high-energy heavy-ion collisions. We do a detailed comparison of pre-equilibrium photon rates to the thermal photon production. We show that the photon spectrum radiated from a hydrodynamic attractor evolution satisfies a simple scaling form in terms of the specific shear viscosity $\eta/s$ and entropy density $dS/d\zeta \sim {\scriptstyle \left(T\tau^{1/3}\right)^{3/2}}_\infty$. We confirm the analytical predictions with numerical kinetic theory simulations. We use the extracted scaling function to compute the pre-equilibrium photon contribution in $\sqrt{s_{NN}}=2.76\,\text{TeV}$ 0-20\% PbPb collisions. We demonstrate that our matching procedure allows for a smooth switching from pre-equilibrium kinetic to thermal hydrodynamic photon production. Finally, our publicly available implementation can be straightforwardly added to existing heavy ion models.

11.How to measure the spin of invisible states in $e^+e^- \to γ+ X$

Authors:Martin Bauer, Sofie Nordahl Erner

Abstract: We examine the production of an invisible state $X$ together with a photon $e^+e^- \to \gamma +X$ at electron positron colliders and present measurement strategies that can detect the spin of the invisible state as well as the underlying production mechanism, based on the angular distribution of the final state photon, the cross sections for polarized initial states and the photon polarization. Our measurement strategy can be used to identify whether the invisible state is a hidden photon or an axion. The results are compared with a detailed analysis of the Standard Model background and we calculate the sensitivity reach for searches for axions and hidden photons at Belle II.

12.A closer look at dark matter production in exponential growth scenarios

Authors:Disha Bhatia

Abstract: Recently, a new non-thermal mechanism for dark matter production has been proposed which results in its exponential growth with the expansion of the universe. This mechanism works provided a small but non-zero initial dark matter ($\chi$) number density exists in the early universe which scatters of the bath particles ($\phi$) to generate more dark matter particles ($\chi \phi \to \chi \chi$). The process ends when the scattering rate becomes Boltzmann suppressed. The analysis, in literature, is performed on the simplifying assumption of the dark matter phase space tracing the equilibrium distribution of either standard model or a hidden sector bath. Owing to the non-thermal nature of the production mechanism, this assumption may not hold. In this paper, we compute the distribution function of dark matter by solving the Boltzmann-equation at the operator level analytically and/or numerically. We find that the obtained distribution exhibits different behavior from the equilibrium pattern and is sensitive to the mechanism populating the initial density of dark matter. We further show that the exponential growth results only in the scenarios where dark matter phase space follows an equilibrium distribution or in the case where only high momentum modes in the dark matter phase space distribution are populated. In general, the growth of dark matter can be parameterised as an exponential factor i.e. $\exp{[A(x)]}$ where $A(x)$ is sensitive to the details of the model.

1.Compositeness of near-threshold exotic hadrons with decay and coupled-channel effects

Authors:Tomona Kinugawa, Tetsuo Hyodo

Abstract: The near-threshold exotic hadrons such as $T_{cc}$ and $X(3872)$ are naively considered as the hadronic molecular state from the viewpoint of the low-energy universality. However, it is also known that the elementary dominant state is not completely excluded as the internal structure of the near-threshold states. Furthermore, the dominance of molecules is expected to be modified by the decay or coupled channels. We discuss these features of the near-threshold bound states by calculating the compositeness with the effective field theory.

2.Neutrino Mass Sum Rules from Modular $\mathcal{A}_4$ Symmetry

Authors:Salvador Centelles Chuliá, Ranjeet Kumar, Oleg Popov, Rahul Srivastava

Abstract: Modular symmetries offer a dynamic approach to understanding the flavour structure of leptonic mixing. Using the modular $\mathcal{A}_4$ flavour symmetry integrated in a type-II seesaw, we propose a simple and minimalistic model that restricts the neutrino oscillation parameter space and, most importantly, introduces a sum rule in the physical neutrino masses. When combined with the mass squared differences observed in neutrino oscillations, this sum rule determines the absolute neutrino mass scale. This has significant implications for cosmology, neutrinoless double beta decay experiments and direct neutrino mass measurements. In particular, the model predicts $\sum_i m_i \approx 0.1$ eV for both normal and inverted ordering, and thus can be fully probed by the current generation of cosmological probes in the upcoming years.

3.Associated vector meson and bound-free electron-positron pair photoproduction in ultraperipheral $PbPb$ collisions

Authors:Celsina N. Azevedo, Victor P. Goncalves, Bruno D. Moreira

Abstract: In this letter we analyze the associated production of a vector meson with the bound - free $e^+e^-$ process in ultraperipheral $PbPb$ collisions through the double scattering mechanism for the energy of the Large Hadron Collider (LHC). Such process is characterized by the presence of a meson and a positron in the final state and by a forward hydrogen - like ion with a distinct electric charge. We present our predictions for the total cross sections and rapidity distributions considering the rapidity ranges covered by the ALICE and LHCb detectors, which indicate that a future experimental analysis of the $\phi + e^+$ and $J/\Psi + e^+$ final states is feasible.

4.Probing Stochastic Gravitational Wave Background from $SU(5) \times U(1)_χ$ Strings in Light of NANOGrav 15-Year Data

Authors:Waqas Ahmed, Mansoor Ur Rehman, Umer Zubair

Abstract: A realistic model of $SU(5) \times U(1)_{\chi}$, embedded in $SO(10)$ supersymmetric grand unified theory, is investigated for the emergence of a metastable cosmic string network. This network eventually decays via the Schwinger production of monopole-antimonopole pairs, subsequently generating a stochastic gravitational wave background that is compatible with the NANOGrav 15-year data. In order to avoid the monopole problem in the breaking of both $SO(10)$ and $SU(5)$, a non-minimal Higgs inflation scenario is incorporated. The radiative breaking of the $U(1)_{\chi}$ symmetry at a slightly lower scale plays a pivotal role in aligning the string tension parameter with the observable range. The resultant gravitational wave spectrum not only accounts for the signal observed in the most recent pulsar timing array (PTA) experiments but is also accessible to both current and future ground-based and space-based experiments.

5.Deep Exclusive Meson Production as a probe to the puzzle of $Λ$ hyperon polarization

Authors:Zhoudunming Tu

Abstract: In the 1970s, an unexpected transverse $\Lambda$ polarization in unpolarized proton-Beryllium collisions was discovered, which initiated extensive studies on spin phenomena in high-energy physics. Over the past five decades, similar transverse $\Lambda$ polarization has been observed across various collision systems, including lepton-hadron deep inelastic scattering, hadron-hadron collisions, and electron-positron collisions. Despite numerous promising theoretical models, the fundamental mechanism underlying this polarization phenomenon remains inconclusive to this day. However, in both longitudinally and transversely polarized lepton-hadron and hadron-hadron collisions, it is found that the $\Lambda$ hyperon is not polarized with respect to the initial parton spin direction. How the $\Lambda$ hyperon acquires its spin has become one of the most crucial questions to address in order to resolve this puzzle. In this Letter, I propose to use an exclusive process that can be measured at the Electron-Ion Collider, the Deep Exclusive Meson Production, to explicitly test the mechanism of $\Lambda$ polarization. The outcomes of this experimental measurement are anticipated to unveil the dominant mechanism by which $\Lambda$ obtains its spin, eliminating many of the ambiguities that have been encountered in previous studies. Finally, experimental challenges and requirements will be discussed.

6.Phenomenological profile of scotogenic fermionic dark matter

Authors:Anirban Karan, Soumya Sadhukhan, José W. F. Valle

Abstract: We consider the possibility that neutrino masses arise from the exchange of dark matter states. We examine in detail the phenomenology of fermionic dark matter in the singlet-triplet scotogenic reference model. We explore the case of singlet-like fermionic dark matter, examining in detail all co-annihilation effects relevant for determining its relic abundance, including fermion-fermion as well as scalar-fermion co-annihilation, which are properly taken into account. Although this in principle allows for dark matter below 60 GeV, the latter is in conflict with charged lepton flavour violation (cLFV) and/or collider physics constraints. We examine the prospects for direct dark matter detection in upcoming experiments up to 10 TeV. Fermion-scalar coannihilation is needed to obtain viable fermionic dark matter in the 60-100 GeV mass range. Fermion-fermion and fermion-scalar coannihilation play complementary roles in different parameter regions above 100 GeV.

7.Early Universe hypercharge breaking and neutrino mass generation

Authors:Sergio López-Zurdo, Álvaro Lozano-Onrubia, Luca Merlo, José Miguel No

Abstract: We show that the conditions allowing for a spontaneous breaking of the $U(1)_Y$ hypercharge gauge symmetry of the Standard Model (SM) in the early Universe are generically present in extensions of the SM addressing the generation of light neutrino masses via radiative contributions. In such scenarios, the breaking of (hyper)charge at high-temperatures yields new possibilities for explaining the observed matter-antimatter asymmetry of the Universe. Considering for concreteness the Zee-Babu radiative neutrino mass generation model, we show that a period of hypercharge breaking prior to the electroweak phase transition could allow for successful baryogenesis via a non-conventional leptogenesis mechanism, based on the presence of charge-breaking masses for the SM leptons in the early Universe.

1.Chiral kinetic theory with self-energy corrections and neutrino spin Hall effect

Authors:Naoki Yamamoto, Di-Lun Yang

Abstract: We systematically derive the chiral kinetic theory for chiral fermions with collisions, including the self-energy corrections, from quantum field theories. We find that the Wigner functions and chiral kinetic equations receive both the classical and quantum corrections from the self-energies and their spacetime gradients. We also apply this formalism to study non-equilibrium neutrino transport due to the interaction with thermalized electrons, as realized in core-collapse supernovae. We derive neutrino currents along magnetic fields and neutrino spin Hall effect induced by temperature and chemical potential gradients of electrons at first order in the Fermi constant $G_{\rm F}$ for anisotropic neutrino distributions.

2.Generalized parton distributions of gluon in proton: a light-front quantization approach

Authors:Bolang Lin, Sreeraj Nair, Siqi Xu, Zhi Hu, Chandan Mondal, Xingbo Zhao, James P. Vary

Abstract: We solve for the gluon generalized parton distributions (GPDs) inside the proton, focusing specifically on leading twist chiral-even GPDs. We obtain and employ the light-front wavefunctions (LFWFs) of the proton from a light-front quantized Hamiltonian with Quantum Chromodynamics input using basis light-front quantization (BLFQ). Our investigation incorporates the valence Fock sector with three constituent quarks and an additional Fock sector, encompassing three quarks and a dynamical gluon. We examine the GPDs within impact parameter space and evaluate the $x$-dependence of the transverse square radius. We find that the transverse size of the gluon at lower-$x$ is larger than that of the quark, while it exhibits opposite behavior at large-$x$. Using the proton spin sum rule, we also determine the relative contributions of quarks and the gluon to the total angular momentum of the proton.

3.Hierarchical High-Point Energy Flow Network for Jet Tagging

Authors:Wei Shen, Daohan Wang, Jin Min Yang

Abstract: Jet substructure observable basis is a systematic and powerful tool for analyzing the internal energy distribution of constituent particles within a jet. In this work, we propose a novel method to insert neural networks into jet substructure basis as a simple yet efficient interpretable IRC-safe deep learning framework to discover discriminative jet observables. The Energy Flow Polynomial (EFP) could be computed with a certain summation order, resulting in a reorganized form which exhibits hierarchical IRC-safety. Thus inserting non-linear functions after the separate summation could significantly extend the scope of IRC-safe jet substructure observables, where neural networks can come into play as an important role. Based on the structure of the simplest class of EFPs which corresponds to path graphs, we propose the Hierarchical Energy Flow Networks and the Local Hierarchical Energy Flow Networks. These two architectures exhibit remarkable discrimination performance on the top tagging dataset and quark-gluon dataset compared to other benchmark algorithms even only utilizing the kinematic information of constituent particles.

4.Isosinglet vectorlike leptons at $e^+e^-$ colliders

Authors:Prudhvi N. Bhattiprolu, Stephen P. Martin, Aaron Pierce

Abstract: We study weak isosinglet vectorlike leptons that decay through a small mixing with the tau lepton, for which the discovery and exclusion reaches of the Large Hadron Collider and future proposed hadron colliders are limited. We show how an $e^+ e^-$ collider may act as a discovery machine for these $\tau^{\prime}$ particles, demonstrate that the $\tau^{\prime}$ mass peak can be reconstructed in a variety of distinct signal regions, and explain how the $\tau^{\prime}$ branching ratios may be measured.

5.Comments on "On the Dirac-Majorana neutrinos distinction in four-body decays" (arXiv:2305.14140 [hep-ph])

Authors:C. S. Kim, M. V. N. Murthy, Dibyakrupa Sahoo

Abstract: In arXiv:2305.14140 [hep-ph] the authors analyze the radiative leptonic decay $\ell^- \to \nu_\ell \, \overline{\nu}_{\ell'} \, \ell^{\prime -} \, \gamma$ to distinguish between Dirac and Majorana nature of neutrinos. They utilize the back-to-back kinematics for this purpose, a special kinematic configuration which we first proposed in our paper arXiv:2106.11785 [hep-ph]. However, their analysis suffers from two fundamental issues: (1) anti-symmetrization of their amplitude and (2) their study of the special back-to-back configuration. This makes their conclusion and comments invalid and untenable.

6.Energy dependence of proton-proton elastic scattering at large momentum transfer

Authors:Erasmo Ferreira, Anderson Kendi Kohara

Abstract: The measurements of proton-proton elastic scattering for large momentum transfer at energies in the range $\approx$ 20 to 60 GeV show a simple behaviour of form $d \sigma/dt \approx {\rm const}~|t|^{-8}$, apparently with no energy dependence. In the present work detailed analysis of the data shows a decrease of the magnitude of the tail with the energy, still with preservation of the power $|t|^{-8}$. The analysis allows the definition of a band for the energy dependence with the form of a power of the strong coupling $\alpha_S^{1.57}$. The rate of decrease describes very well the data at the distant energy $\sqrt{s}$ = 13 TeV, with reduction of the cross section by a factor 5.71. This result gives prediction for new experiments at high energies, and opens important question for theoretical investigation.

7.Detecting Ultra-light Dark Matter with Stimulated Annihilation

Authors:Yuanlin Gong, Xin Liu, Lei Wu, Qiaoli Yang, Bin Zhu

Abstract: Ultra-light Dark Matter (ULDM) is one of the most promising DM candidates. In the presence of background photon radiation, the annihilation rate of the ULDM can be greatly enhanced due to the Bose enhancement. We propose to utilize such stimulated annihilation to probe the ULDM by emitting a beam of radio into the space. This could lead to a distinctive reflected electromagnetic wave with an angular frequency equal to the ULDM mass. We show that low-frequency radio telescopes, such as LOFAR, UTR-2 and ngBOLO, can offer a new avenue of detecting this signal, especially for the Earth halo model. With a power of 50 MW emitter, the expected limits could be several orders of magnitude stronger than that from Big Bang nucleosynthesis (BBN) in the ULDM mass $m_\phi$ range, $2.07 \times 10^{-8}\mathrm{~eV} \sim 4.5 \times 10^{-8}\mathrm{~eV}$.

1.New insights into the nature of the $Λ(1380)$ and $Λ(1405)$ resonances away from the SU(3) limit

Authors:Feng-Kun Guo, Yuki Kamiya, Maxim Mai, Ulf-G. Meißner

Abstract: Starting from the SU(3) limit, we consider the nature of the dynamically generated resonances $\Lambda(1380)$, $\Lambda(1405)$ and $\Lambda(1680)$ as the pion and kaon masses are tuned to their physical values. We show that the accidental symmetry of the two octets due to the leading order Weinberg-Tomozawa term is broken by the next-to-leading order terms. Most interestingly, we observe an interchange of the two trajectories of the $\Lambda(1380)$ and the $\Lambda(1405)$ away from the SU(3) limit at next-to-leading order. This remarkable phenomenon can be investigated using lattice QCD calculations that start from the SU(3) limit.

2.The properties of the $S$-wave $D_s\bar{D}_s$ bound state

Authors:Jing-Juan Qi, Zhen-Yang Wang, Zhu-Feng Zhang, Xin-Heng Guo

Abstract: In this work, we investigate possible bound states of the $D_s\bar{D}_s$ system in the Bethe-Salpeter formalism in the ladder and instantaneous approximations. By numerically solving the Bethe-Salpeter equation with a kernel that includes the contributions from $\phi$ and $J/\psi$ exchanges, we confirm the existence of a bound state in the $D_s\bar{D}_s$ system. We further investigate the partial decay widths of the $D_s\bar{D}_s$ bound state into $D\bar{D}$, $\eta_c\eta$, and $J/\psi\omega$, finding that these partial widths are sensitive to the parameter $\alpha$ in our model. Notably, we observe that the dominant decay channel for the $D_s\bar{D}_s$ bound state is that into $D\bar{D}$.

3.Nonleptonic two-body weak decays of charmed baryons

Authors:Chia-Wei Liu

Abstract: We systematically analyze the two-body nonleptonic weak decays of charmed baryons, employing the pole approximation in tandem with the $SU(3)_F$ symmetry. Leveraging the K\"orner-Patti-Woo theorem, we demonstrate a significant reduction in the number of free parameters. Within the general pole scenario, we successfully explain most of the experimental data of ${\bf B}_c^A \to {\bf B}_nP$, though some inconsistencies are detected and recommended for reexamination in future research. Assuming the dominance of low-lying intermediate baryons, we are able to make novel predictions for decay channels such as $\Omega_c^0 \to {\bf B}_n P$ and ${\bf B}_{cc}\to {\bf B}_c^{A,S} P$. Here, ${\bf B}_n$, ${\bf B}_{c}^A$, ${\bf B}_c^S$ and ${\bf B}_{cc}$ are the low-lying octet, antitriplet charmed, sextet charmed and doubly charmed baryons, respectively, and $P$ is the pseudoscalar meson. Our findings also reveal that the fitted effective Wilson coefficient ${\cal C}_+=0.469$ is notably smaller than the na\"ive expectation, and the low-lying pole scenario fails to account for ${\cal B}(\Lambda_c^+ \to n \pi^+ , \Xi^0 K^+)$ , despite consistencies with the soft meson limit. We further recommend the decay channel $\Xi_{cc}^+ \to \Xi_c^0 \pi^+ \to \Xi^- \pi^+\pi^+\pi^+\pi^-$ for exploring evidence of $\Xi_{cc}^+$, estimating the branching fraction at $(1.1\pm 0.6)\times 10^{-3}$. The predictions for nonleptonic weak decay channels are compiled in the appendices, providing valuable references for future experimental validation.

4.Current status on pair-produced muon-philic vectorlike leptons in multilepton channels at the LHC

Authors:Junichiro Kawamura, Seodong Shin

Abstract: In this work, we obtain the current limits on the pair production of vectorlike leptons decaying to a Standard Model gauge boson and a lepton in the second generation using the Run-2 data at the LHC. Since there is no dedicated search, we recast the ATLAS analyses searching for the type-III seesaw heavy leptons in the multi-lepton channels. There is no limit for the $SU(2)_L$ singlet vectorlike lepton beyond about 100 GeV, while the limit is about 780 GeV for the doublet one. Thus, dedicated searches for the vectorlike leptons are necessary, especially for the singlet one. We also study the general cases of the vectorlike lepton decays and future sensitivities the HL-LHC.

5.Renormalization of a Standard Model Extension with a Dark Abelian Sector and Predictions for the W-Boson Mass

Authors:Stefan Dittmaier, Jonas Rehberg, Heidi Rzehak

Abstract: The described Dark Abelian Sector Model (DASM) extends the Standard Model (SM) by a ``dark'' sector containing a spontaneously broken $U(1)_\text{d}$ gauge group. Keeping this dark sector quite generic we only add one additional Higgs boson, one Dirac fermion, and right-handed SM-like neutrinos to the SM. Using the only two singlet operators of the SM with dimension less than 4 (the $U(1)_\text{Y}$ field-strength tensor and the SM Higgs mass operator $|\Phi|^2$) as well as the right-handed neutrino fields we open up three portals to the dark sector. Dark sectors, such as the one of the DASM, that introduce an additional Higgs boson $\text{H}$ as well as an additional $\text{Z}'$ gauge boson can have a large influence on the predictions for electroweak precision observables and even accommodate possible dark matter candidates. We consider one of the two Higgs bosons to be the known $125\,\text{GeV}$ Higgs boson and parameterize the extension of the scalar sector by the mass of the second Higgs boson, the Higgs mixing angle, and a Higgs self-coupling. We do not assume any mass hierarchy in the gauge sector and use the mass of the additional $\text{Z}'$ boson and a corresponding gauge-boson mixing angle to parameterize the extension of the gauge sector. The fermion sector is parameterized by the mass of the additional fermion and a fermion mixing angle. We describe an on-shell as well as an $\overline{\text{MS}}$ renormalization scheme for the DASM sectors and give explicit results for the renormalization constants at the 1-loop level, and, thus, prepare the ground for full NLO predictions for collider observables in the DASM. As a first example, we provide the DASM prediction for the W-boson mass derived from muon decay.

6.Cosmic inflation and $(g-2)_μ$ in minimal gauged $L_μ-L_τ$ model

Authors:Arnab Paul, Sourov Roy, Abhijit Kumar Saha

Abstract: The minimal $U(1)_{L_\mu-L_\tau}$ gauge symmetry extended Standard Model (SM) is a well motivated framework that resolves the discrepancy between the theoretical prediction and experimental observation of muon anomalous magnetic moment. We envisage the possibility of identifying the beyond Standard Model Higgs of $U(1)_{L_\mu-L_\tau}$ sector, non-minimally coupled to gravity, as the inflaton in the early universe, while being consistent with the $(g-2)_\mu$ data. Although the structure seems to be trivial, we observe that taking into consideration of a complete cosmological history starting from inflation through the reheating phase to late-time epoch along with existing constraints on $U(1)_{L_\mu-L_\tau}$ model parameters leave us a small window of allowed reheating temperature. This further results into restriction of $(n_s-r)$ plane which is far severe than the one in a generic non-minimal quartic inflationary set up.

1.Exclusive quarkonium photoproduction in $A$+$A$ UPCs at the LHC in NLO pQCD

Authors:Kari J. Eskola, Christopher A. Flett, Vadim Guzey, Topi Löytäinen, Hannu Paukkunen

Abstract: We present the first study of coherent exclusive quarkonium ($J/\psi$, $\Upsilon$) photoproduction in ultraperipheral nucleus-nucleus collisions (UPCs) at the LHC in the framework of collinear factorization and next-to-leading order (NLO) perturbative QCD (pQCD). We make NLO predictions for the $J/\psi$ and $\Upsilon$ rapidity distributions for lead (Pb) and oxygen (O) beams, and quantify their dependence on the factorization/renormalization scale, nuclear parton distribution functions (PDFs) and their uncertainties, and on differences between nuclear PDFs and generalized parton distribution functions (GPDs). We show that within the PDF-originating uncertainties our approach provides a good description of the available $J/\psi$ photoproduction data in Pb+Pb UPCs at the LHC but that the scale uncertainty is significant. We demonstrate that at NLO pQCD the quark contributions are important in the $J/\psi$ case but that gluons clearly dominate the $\Upsilon$ cross sections. We also study how the scale dependence could be tamed by considering O+O/Pb+Pb ratios of the exclusive $J/\psi$ UPC cross sections, and how HERA and p+p/Pb LHC data can help in obtaining better-controlled NLO predictions in the $\Upsilon$ case.

2.Dark Coloured Scalars Impact on Single and Di-Higgs Production at the LHC

Authors:Pedro Gabriel, Margarete Mühlleitner, Daniel Neacsu, Rui Santos

Abstract: The search for Dark Matter (DM) at colliders is primarily pursued via the detection of missing energy in particular final states. These searches are based on the production and decay processes where final states include DM particles and at least one Standard Model (SM) particle. DM will then reveal itself as missing energy. An alternative form to get a hint of a dark sector is via loop contribution to SM processes. In this case, it is not even relevant if the new particles have their origin in the dark sector of the model. In this work we discuss the impact of an arbitrary number of coloured scalars in single Higgs and double Higgs production at the Large Hadron Collider (LHC), and we show their complementarity. We determine the range of variation of the corrections relative to the SM for an arbitrary number of coloured scalars $n$, and discuss in more detail the cases $n=1$ and $n=2$.

3.Constraining inverse moment of $B$-meson distribution amplitude using Lattice QCD data

Authors:Rusa Mandal, Soumitra Nandi, Ipsita Ray

Abstract: We constrain the inverse moment of the $B$-meson light-cone distribution amplitude (LCDA), $\lambda_B$ in heavy quark effective theory, using form factor estimates from Lattice QCD collaboration. The estimation of the parameter $\lambda_B$ has, until now, relied solely on QCD sum rule methods and deals with significant uncertainty. In this work, we express the form factors for the $B \to K$ channel, calculated within the light-cone sum rule (LCSR) approach, in terms of the $B$-meson LCDAs. By incorporating recent Lattice results from the HPQCD collaboration for the $B \to K$ form factors at zero momentum transfer ($q^2$ = 0), we impose constraints on this parameter. Consequently, we achieve a twofold reduction in uncertainty compared to the QCD sum rule estimate, yielding $\lambda_B=338\pm 68$ MeV, when the $B$-meson LCDAs are expressed in the Exponential model. Additionally, we compare the form factor predictions, using the constrained $\lambda_B$ value, with the earlier analyses for other channels as well, such as $B\to \pi$ and $B \to D$.

4.Dibaryons and where to find them

Authors:M. Bashkanov, D. P. Watts, G. Clash, M. Mocanu, M. Nicol

Abstract: In recent years there has been tremendous progress in the investigation of bound systems of quarks with multiplicities beyond the more usual two- and three-quark systems. Experimental and theoretical progress has been made in the four-, five- and even six-quark sectors. In this paper, we review the possible lightest six-quark states using a simple ansatz based on SU(3) symmetry and evaluate the most promising decay branches. The work will be useful to help focus future experimental searches in this six-quark sector.

5.Coherently diffractive dissociation in electron-hadron collisions: from HERA to the future EIC

Authors:Tuomas Lappi, Anh Dung Le, Heikki Mäntysaari

Abstract: We present numerical results on diffractive dissociation with large invariant mass diffractive final states in the scattering of an electron off a hadron. The diffractive large-mass resummation is performed using the nonlinear Kovchegov-Levin equation, taking into account running coupling corrections. For the scattering off the proton, a (modified) McLerran-Venugopalan amplitude is used as the initial condition for the nonlinear evolution, with free parameters being constrained by the HERA inclusive data. The results show a reasonable description of the HERA diffractive structure function data at moderately large diffractive mass when the impact parameter profile is constrained by the low-mass diffractive cross section data. The calculation is extended to nuclear scattering, where the initial condition is generalized from the proton case employing the optical Glauber model. The nonlinear large-mass resummation predicts a strong nuclear modification in diffractive scattering off a nuclear target in kinematics accessible at the future Electron-Ion collider.

6.Inflation, superheavy metastable strings and gravitational waves in non-supersymmetric flipped SU(5)

Authors:George Lazarides, Rinku Maji, Ahmad Moursy, Qaisar Shafi

Abstract: Motivated by the NANOGrav 15 year data and other recent investigations of stochastic gravitational background radiation based on pulsar timing arrays, we show how superheavy strings survive inflation but the slightly heavier monopoles do not in a non-supersymmetric hybrid inflation model based on flipped $SU(5)$. With the dimensionless string tension parameter $G \mu\approx 10^{-7}-10^{-6}$, the gravitational wave spectrum emitted by the strings, which are metastable due to breaking caused by monopole-antimonopole quantum mechanical tunneling, is compatible with the latest NANOGrav measurement as well as the advanced LIGO-VIRGO third run data. For $G \mu \approx 10^{-6}$, the string network undergoes about 30 $e$-foldings of inflation which suppresses the spectrum in the LIGO-VIRGO frequency range. With the symmetry breaking chain $SU(5) \times U(1)_X \to SU(3)_c \times SU(2)_L\times U(1)_Z \times U(1)_X \to SU(3)_c \times SU(2)_L \times U(1)_ Y$, the estimated proton lifetime is of order $10^{34}-10^{36}$ yrs.

7.Handbook of the analytic and expansion formulae for the muon $g-2$ anomaly

Authors:Shi-Ping He

Abstract: Since announcement of the muon $g-2$ anomaly, plenty of papers have devoted to this anomaly. The approximate formulae are always adopted when determining the new physics contributions to $(g-2)_{\mu}$, while clear scope of applications are always absent. This manuscript is dedicated to the comprehensive analytical results and approximations for the canonical interactions at one-loop level, which can be a useful handbook for the model builders. Here, we only collect the analytic and approximate expressions for the scalar mediator case. For the expressions of vector mediator case, they will appear in the future.

8.Magnetic monopole meets primordial black hole: An extended analysis

Authors:Chen Zhang, Xin Zhang

Abstract: We investigate gravitational capture of magnetic monopoles by primordial black holes (PBH) that evaporate before Big Bang Nucleosynthesis (BBN), a hypothetical process which was once proposed as an alternative solution to the monopole problem. Magnetic monopoles produced in phase transitions of a grand or partially unified gauge theory are considered. We prove analytically that for all extended PBH mass functions that preserve radiation domination, it is impossible to reduce the monopole abundance via gravitational capture by PBHs to values significantly below the one set by monopole annihilation (or below its initial abundance if it is smaller), regardless of the nature of the capture process (diffusive or non-diffusive). Therefore, the monopole problem cannot be solved by PBH capture in a radiation-dominated era in the early universe.

9.Heavy quark diffusion coefficient during hydrodynamization -- non-equilibrium vs. equilibrium

Authors:Kirill Boguslavski, Aleksi Kurkela, Tuomas Lappi, Florian Lindenbauer, Jarkko Peuron

Abstract: We compute the heavy quark momentum diffusion coefficient using effective kinetic theory for a system going through bottom-up isotropization until approximate hydrodynamization. We find that when comparing the nonthermal diffusion coefficient to the thermal one for the same energy density, the observed deviations throughout the whole evolution are within 30% from the thermal value. For thermal systems matched to other quantities we observe considerably larger deviations. We also observe that the diffusion coefficient in the transverse direction dominates at large occupation number, whereas for an underoccupied system the longitudinal diffusion coefficient dominates. Similarly, we study the jet quenching parameter, where we obtain a smooth evolution connecting the large values of the glasma phase with the smaller values in the hydrodynamical regime.

10.Whole $B_c$ meson spectroscopy under the unquenched picture

Authors:Xue-Jian Li, Yu-Shuai Li, Fu-Lai Wang, Xiang Liu

Abstract: In this work, we investigate the spectroscopy of higher $B_c$ mesons, with a special focus on the consideration of the unquenched effects. To account for such effects, we employ the modified Godfrey-Isgur model and introduce a screening potential. The resulting mass spectrum of the concerned higher $B_c$ states is then presented, showing significant deviations after considering the unquenched effects. This emphasizes the importance of considering the unquenched effects when studying of the higher $B_c$ mesons. Furthermore, we determine the corresponding spatial wave functions of these $B_c$ mesons, which have practical applications in subsequent studies of their decays. These decays include two-body Okuba-Zweig-Iizuka allowed strong decays, dipion transitions between $B_c$ mesons, radiative decays, and some typical weak decays. With the ongoing high-luminosity upgrade of the Large Hadron Collider, we expect the discovery of additional $B_c$ states in the near future. The knowledge gained from the mass spectrum and the different decay modes will undoubtedly provide valuable insights for future experimental explorations of these higher $B_c$ mesons.

11.Constraints on holographic QCD phase transitions from PTA observations

Authors:Song He, Li Li, Sai Wang, Shao-Jiang Wang

Abstract: The underlying physics of QCD phase transition in the early Universe remains largely unknown due to its strong-coupling nature during the quark-gluon plasma/hadron gas transition, yet a holographic model has been proposed to quantitatively fit the lattice QCD data while with its duration of the first-order phase transition (FoPT) left undetermined. At specific baryon chemical potential, the first-order QCD phase transition agrees with the observational constraint of baryon asymmetry. It therefore provides a scenario for phase transition gravitational waves (GWs) within the Standard Model of particle physics. If these background GWs could contribute dominantly to the recently claimed common-spectrum red noise from pulsar timing array (PTA) observations, the duration of this FoPT can be well constrained but disfavored by the constraints from curvature perturbations. However, the associated primordial black holes are still allowed by current observations. Therefore, either the QCD phase transition is not described by our holographic model or the other GW sources must be presented to dominate over the GWs from this FoPT.

12.Can Planet 9 be an Axion Star?

Authors:Haoran Di, Haihao Shi

Abstract: The anomalous orbits of Trans-Neptunian Objects (TNOs) can be explained by the Planet 9 hypothesis. We propose that the Planet 9 can be an axion star. Axion stars are gravitational bound clusters condensed by QCD axions or axion-like particles (ALPs), which we call axions for brevity. We find that the probability of capturing an axion star is the same order of magnitude as the probability of capturing an free floating planet (FFP), and even higher for the case of axion star, with axion star mass $5M_\oplus$ and $\Omega_{\rm{AS}}/\Omega_{\rm{DM}}\simeq 1/10$. Although axion star can emit monochromatic signals through two-photon decay, we find that the frequency of decay photon is either not within the frequency range of the radio telescope, or the decay signal is too weak to be detected. Therefore, if Planet 9 is composed by an axion star, it will be difficult to distinguish it from an isolated primordial black hole by spontaneous decay of axion.

13.Heavy neutrino-antineutrino oscillations at the FCC-ee

Authors:Stefan Antusch, Jan Hajer, Bruno M. S. Oliveira

Abstract: We discuss the impact of heavy neutrino-antineutrino oscillations (NNOs) on heavy neutral lepton (HNL) searches at proposed electron-positron colliders such as the future circular $e^+e^-$ collider (FCC-ee). During the $Z$ pole run, HNLs can be produced alongside a light neutrino or antineutrino that escapes detection and can decay into a charged lepton or antilepton together with an off-shell $W$ boson. In this case, signals of lepton number violation only show up in the final state distributions. We discuss how NNOs, a typical feature of collider-testable low-scale seesaw models where the heavy neutrinos form pseudo-Dirac pairs, modify such final state distributions. For example, the forward-backward asymmetry (FBA) of the reconstructed heavy (anti)neutrinos develops an oscillatory dependence on the HNL lifetime. We show that these oscillations can be resolvable for long-lived HNLs. We also discuss that when the NNOs are not resolvable, they can nevertheless significantly modify the theory predictions for FBAs and observables such as the ratio of the total number of HNL decays into $\ell^-$ over ones into $\ell^+$, in an interval of the angle~$\theta$ between the HNL and the beam axis. Our results show that NNOs should be included in collider simulations of HNLs at the FCCee.

14.Deconfinement transition in the revolving bag model

Authors:Kazuya Mameda, Keiya Takizawa

Abstract: Based on the bag model, we revisit the deconfinement phase transition under rotation. On top of the usual rotational energy for noninteracting particles, we perturbatively analyze the revolution effect of the hadron bag, i.e., of the potential confining quarks. The revolution effect can be phenomenologically translated into the rotational correction to the QCD vacuum energy or the gluon condensate. We demonstrate that if the revolution effect is (is not) taken into account, the transition temperature increases (decreases) as the angular velocity increased. The `revolving bag model' provides a feasible explanation of the recent lattice simulations, contrary to effective models, showing that rotation favors the confined phase.

1.$A_{5}$ symmetry and deviation from Golden Ratio mixing

Authors:Victoria Puyam, N. Nimai Singh

Abstract: We use $A_{5}$ discrete symmetry group to construct a neutrino mass model that can reproduce deviation from the exact golden ratio mixing. Here, we obtain the neutrino masses through Type-I seesaw mechanism. The contribution from charged lepton sector gives the necessary deviation required to produce non-zero $\theta_{13}$. More specifically, a definite pattern of charged lepton mass matrix predicted by the model controls the lepton mixing. By taking the observed $\theta_{13}$ as input value we can obtain the value of all the mixing angles and Dirac CP violating phase within the current experimental bounds.

2.Computing Mellin representations and asymptotics of nested binomial sums in a symbolic way: the RICA package

Authors:Johannes Bluemlein, Nikolai Fadeev, Carsten Schneider

Abstract: Nested binomial sums form a particular class of sums that arise in the context of particle physics computations at higher orders in perturbation theory within QCD and QED, but that are also mathematically relevant, e.g., in combinatorics. We present the package RICA (Rule Induced Convolutions for Asymptotics), which aims at calculating Mellin representations and asymptotic expansions at infinity of those objects. These representations are of particular interest to perform analytic continuations of such sums.

3.Demystifying the nature of nuclear modification factor for upcoming O-O collisions at LHC energies using a transport model

Authors:Debadatta Behera, Suman Deb, Captain R. Singh, Raghunath Sahoo

Abstract: The present work focuses on Oxygen-Oxygen (O-O) collisions, which are planned at the CERN Large Hadron Collider. Oxygen, being a doubly magic number nucleus, has some very unique features. This study attempts to probe the exotic state of QCD matter in O-O collisions. Additionally, the role of different nuclear density profiles in governing the final state dynamics in ultra-relativistic nuclear collisions is also explored. Using a multi-phase transport (AMPT) model, we obtain the nuclear modification factor ($\rm R_{\rm AA}$ ) for all charged hadrons and identified particles for O-O collisions at $\sqrt{s_{\rm{NN}}}$ = 7 TeV. Furthermore, we investigate the behavior of $\rm R_{\rm AA}$ as a function of transverse momentum ($\rm p_{\rm T}$) for three centralities (most-central, mid-central, and peripheral) considering both $\alpha$-cluster and Woods-Saxon nuclear density profiles. We also extend this work to study the rapidity dependence of $\rm R_{\rm AA}$ for all charged hadrons. To better under our findings of O-O collisions, the results are confronted with the available data of $\rm R_{\rm AA}$ for Pb-Pb collisions. The present study sheds light on particle production mechanisms, emphasizing factors influencing particle yield from pre-collision to post-collision stages in the context of O-O collisions.

4.Naturally small neutrino mass with asymptotic safety and gravitational-wave signatures

Authors:Abhishek Chikkaballi, Kamila Kowalska, Enrico Maria Sessolo

Abstract: We revisit the dynamical generation of an arbitrarily small neutrino Yukawa coupling in the Standard Model with trans-Planckian asymptotic safety and apply the same mechanism to the gauged $B-L$ model. We show that thanks to the presence of additional irrelevant couplings, the described neutrino-mass generation in the $B-L$ model is potentially more in line with existing theoretical calculations in quantum gravity. Interestingly, the model can accommodate, in full naturalness and without extensions, the possibility of purely Dirac, pseudo-Dirac, and Majorana neutrinos with any see-saw scale. We investigate eventual distinctive signatures of these cases in the detection of gravitational waves from first-order phase transitions. We find that, while it is easy to produce a signal observable in new-generation space interferometers, its discriminating features are washed out by the strong dependence of the gravitational-wave spectrum on the relevant parameters of the scalar potential.

5.Molecular components in the $J/ψ$ and the $ρ$-$π$ puzzle

Authors:Xing-Dao Guo, Dian-Yong Chen, Xue-Qian Li, Zhong-Yuan Yuan, Shijin Sang

Abstract: Motivated by the large branching fractions of $J/\psi \to f_0 (1710) \omega/f_0(1710) \phi$ and the light exotic candidates, we find that there may exist molecular states composed of $f_0(1710) \omega$ and $f_0 (1710) \phi$, which correspond to $X(2440)$ and $X(2680)$ observed in a few decades before. The branching fraction of $X(2440)$ and $X(2680)$ to various $PV$ channels and $KK\omega(\phi)$ channels are estimated in the molecular scenario. In addition, the large branching fractions of $J/\psi \to f_0 (1710) \omega/f_0(1710) \phi$ indicate the sizable molecular components in the $J/\psi$ state. Thus, we consider the $J/\psi$ as the supperposition of $c\bar{c}(1S)$, $f_0(1710) \omega$ and $f_0 (1710) \phi$ molecular states, and these molecular components have significant impact on the light hadron decays of $J/\psi$, which may shield light on the long standing $\rho-\pi$ puzzle.

6.An effective gauge field theory of the nucleon interactions

Authors:Eduard Boos

Abstract: We discuss the possibility of constructing an effective gauge field theory of the nucleon interations based on the ideas of isotopic invariance as well as hypercharge invariance as a local gauge symmetry and spontaneous breaking of this symmetry. The constructed model predicts the structure of interactions of protons and neutrons with $\rho$- and $\sigma$-mesons, with pi-mesons and photons, as well as interactions of these particles with each other. The Lagrangian of the model consists of several parts parts involving dimension 4 and 5 gauge invariant operators. Feynman rules for physical degrees of freedom as follow from the Lagrangian define the structure of diagrams for one-boson exchanges between nucleons predicting the internucleon one-boson exchange potential as well as nucleon scattering amplitudes. The range of applicability of the model is discussed and estimates are made of the resulting coupling constants. The model predicts the mass of the neutral $\rho^0$-meson to be about $1\,MeV$ larger than the mass of the charged mesons $\rho^{\pm}$. The vector $\omega$-meson, which is a sterile particle with respect to the considered gauge group $SU_I(2)\times U_Y(1)$, can be added to the scheme by means of a gauge-invariant operator of dimension 5, as shown in Appendix ~A.

7.GRB221009A events from the mediator of dark matter self-interactions

Authors:Debasish Borah, Satyabrata Mahapatra, Narendra Sahu, Vicky Singh Thounaojam

Abstract: In this work, we explore the intriguing possibility of connecting self-interacting dark matter (SIDM) with the recently observed exceptionally bright and long-duration Gamma Ray Burst (GRB221009A). The proposed minimal scenario involves a light scalar mediator, simultaneously enabling dark matter (DM) self-interaction and explaining the observed very high energy (VHE) photons from GRB221009A reported by LHAASO's data. The scalar's mixing with the standard model (SM) Higgs boson allows for its production at the GRB site, which will then propagate escaping attenuation by the extra-galactic background light (EBL). These scalars, if highly boosted, have the potential to explain LHAASO's data. Moreover, the same mixing also facilitates DM-nucleon or DM-electron scatterings at terrestrial detectors, linking SIDM phenomenology to the GRB221009A events. This manuscript presents the parameter space meeting all constraints and offers an exciting opportunity to explore SIDM in future direct search experiments using insights from the GRB observation.

8.Positivity and the Electroweak Hierarchy

Authors:Joe Davighi, Scott Melville, Ken Mimasu, Tevong You

Abstract: We point out that an unnatural hierarchy between certain higher-dimensional operator coefficients in a low-energy Effective Field Theory (EFT) would automatically imply that the Higgs' vacuum expectation value is hierarchically smaller than the EFT cut-off, assuming the EFT emerged from a unitary, causal and local UV completion. Future colliders may have the sensitivity to infer such a pattern of coefficients for a little hierarchy with an EFT cut-off up to $\mathcal{O}(10)$ TeV.

1.W boson mass in the NP models with extra $U(1)$ gauge group

Authors:Jin-Lei Yang, Zhao-Feng Ge, Xiu-Yi Yang, Sheng-Kai Cui, Tai-Fu Feng

Abstract: The precise measurement of the W boson mass is closely related to the contributions of new physics (NP), which can significantly constrain the parameter space of NP models, particularly those with an additional $U(1)$ local gauge group. The inclusion of a new $Z'$ gauge boson and gauge couplings in these models can contribute to the oblique parameters $S$, $T$, $U$ and W boson mass at tree level. In this study, we calculate and analyze the oblique parameters $S$, $T$, $U$ and W boson mass in such NP models, taking into account the effects of kinetic mixing, and it is found that the kinetic mixing effects can make significant contributions to these oblique parameters and W boson mass. Based on the obtained numerical results, the recently measured W boson mass at CDF II or ATLAS can be satisfied by choosing appropriate values of gauge coupling constants and extra $U(1)$ group charges of leptons or scalar doublets. In addition, if the leptonic Yukawa couplings are invariant under the extra $U(1)$ local gauge group, the contributions to $S$, $T$, $U$ and W boson mass can be eliminated by redefining the gauge boson fields through eliminating the neutral currents involving charged leptons.

2.Cold quark matter in a quasiparticle model: thermodynamic consistency and stellar properties

Authors:Zhi-Jun Ma, Zhen-Yan Lu, Jian-Feng Xu, Guang-Xiong Peng, Xiangyun Fu, Junnian Wang

Abstract: The strong coupling in the effective quark mass was usually taken as a constant in a quasiparticle model while it is, in fact, running with an energy scale. With a running coupling, however, the thermodynamic inconsistency problem appears in the conventional treatment. We show that the renormalization subtraction point should be taken as a function of the summation of the biquadratic chemical potentials if the quark's current masses vanish, in order to ensure full thermodynamic consistency. Taking the simplest form, we study the properties of up-down ($ud$) quark matter, and confirm that the revised quasiparticle model fulfills the quantitative criteria for thermodynamic consistency. Moreover, we find that the maximum mass of an $ud$ quark star can be larger than two times the solar mass, reaching up to $2.31M_{\odot}$, for reasonable model parameters. However, to further satisfy the upper limit of tidal deformability $\tilde{\Lambda}_{1.4}\leq 580$ observed in the event GW170817, the maximum mass of an $ud$ quark star can only be as large as $2.08M_{\odot}$, namely $M_{\text{max}}\lesssim2.08M_{\odot}$. In other words, our results indicate that the measured tidal deformability for event GW170817 places an upper bound on the maximum mass of $ud$ quark stars, but which does not rule out the possibility of the existence of quark stars composed of $ud$ quark matter, with a mass of about two times the solar mass.

3.Electron $g-2$ corrections from axion dark matter

Authors:Ariel Arza, Jason Evans

Abstract: We consider the effects of a local axion dark matter background on the $g-2$ of the electron. We calculate loop corrections to the photon-electron vertex and determine analytical formulas for the spin and cyclotron frequencies when the electron is in an external magnetic field. By comparing with current measurements of these observables, we are able to place the strongest constraint on the axion-elecron coupling for axion masses below $10^{-15}\text{eV}$.

4.Linear power corrections to top quark pair production in hadron collisions

Authors:Sergei Makarov, Kirill Melnikov, Paolo Nason, Melih A. Ozcelik

Abstract: We compute, in the framework of renormalon calculus, the ${\cal O}(\Lambda_{\rm QCD})$ corrections to the production of $t\bar{t}$ pairs in hadron collisions under the assumption that $q \bar q \to t \bar t$ is the dominant partonic channel. This assumption is not applicable to top quark pair production at the LHC but it is valid for the Tevatron where collisions of protons and anti-protons were studied. We show that the linear power correction to the total $t \bar t$ production cross section vanishes provided one uses a short-distance scheme for the top quark mass. We also derive relatively simple formulas for the power corrections to top quark kinematic distributions. Although small numerically, these power corrections exhibit interesting dependencies on top quark kinematics.

5.Searching for the flavon at current and future colliders

Authors:Eetu Loisa

Abstract: The $ B_3 - L_2$ $ Z' $ model may explain certain features of the fermion mass spectrum as well as the $b \rightarrow s \mu^+ \mu^-$ anomalies. The $ Z' $ acquires its mass via a TeV-scale scalar field, the flavon, whose vacuum expectation value spontaneously breaks the family non-universal gauged $ U(1)_{B_3 - L_2} $ symmetry. We review the key features of the model, with an emphasis on its scalar potential and the flavon field, and use experimental data and perturbativity arguments to place bounds upon the Higgs-flavon mixing angle. Finally, we discuss flavonstrahlung as a means to discover the flavon experimentally and compute flavonstrahlung cross-sections at current and future colliders.

6.Probing invisible dark photon models via atmospheric collisions

Authors:Mingxuan Du, Rundong Fang, Zuowei Liu, Wenxi Lu, Zicheng Ye

Abstract: Atmospheric collisions can copiously produce dark sector particles in the invisible dark photon model, leading to detectable signals in underground neutrino detectors. We consider the dark photon model with the mass mixing mechanism and use the Super-K detector to detect the electron recoil events caused by the atmospherically produced dark sector particles within the model. We find that the combined data from four Super-K runs yield new leading constraints for the invisible dark photon in the mass range of $\sim(0.5-1.4)$ GeV, surpassing the constraints from NA64, BaBar, and searches for millicharged particles.

7.Baryons and tetraquarks using instanton-induced interactions

Authors:Nicholas Miesch, Edward Shuryak, Ismail Zahed

Abstract: We analyze some aspects of the perturbative and non-perturbative interactions in the composition of heavy quarkonia, heavy and light baryons ($ccc$ and $uuu$ ones), as well as all charm tetraquarks ($cc\bar c\bar c$). Using the hyper-spherical approximation and effective radial potentials (in 6 and 9 dimensions, respectively) we derive their spectra and wave functions. In all of the cases, we focus on the splittings between the s-shell levels, which are remarkably insensitive to the quark masses, but proportional to the effective interaction potentials. We use the traditional Cornell-like potentials, and the non-perturbative instanton-induced static potentials, from correlators of two, three and four Wilson lines, and find rather satisfactory description of spectra in all cases.

8.Gauged $SU(3)_F$ and loop induced quark and lepton masses

Authors:Gurucharan Mohanta, Ketan M. Patel

Abstract: We investigate a local $SU(3)_F$ flavour symmetry for its viability in generating the masses for the quarks and charged leptons of the first two families through radiative corrections. Only the third-generation fermions get tree-level masses due to specific choice of the field content and their gauge charges. Unprotected by symmetry, the remaining fermions acquire non-vanishing masses through the quantum corrections induced by the gauge bosons of broken $SU(3)_F$. We show that inter-generational hierarchy between the masses of the first two families arises if the flavour symmetry is broken with an intermediate $SU(2)$ leading to a specific ordering in the masses of the gauge bosons. Based on this scheme, we construct an explicit and predictive model and show its viability in reproducing the realistic charged fermion masses and quark mixing parameters in terms of not-so-hierarchical fundamental couplings. The model leads to the strange quark mass, $m_s \approx 16$ MeV at $M_Z$, which is $\sim 2.4 \sigma$ away from its current central value. Large flavour violations are a generic prediction of the scheme which pushes the masses of the new gauge bosons to $10^3$ TeV or higher.

9.Dark Matter Phenomenology in 2HDMS in light of the 95 GeV excess

Authors:Juhi Dutta, Jayita Lahiri, Cheng Li, Gudrid Moortgat-Pick, Sheikh Farah Tabira, Julia Anabell Ziegler

Abstract: The Two Higgs Doublet model extended with a complex scalar singlet (2HDMS) is a well-motivated Beyond Standard Model candidate addressing several open problems of nature. In this work, we focus on the dark matter (DM) phenomenology of the complex scalar singlet where the real part of the complex scalar obtains a vacuum expectation value. The model is characterized by an enlarged Higgs spectrum comprising six physical Higgs bosons and a pseudoscalar DM candidate. We address the impact of accommodating the 95 GeV excess on the 2HDMS parameter space and DM observables after including all theoretical and experimental constraints. Finally, we look into the prospects of this scenario at HL-LHC and future lepton colliders for a representative benchmark.

10.Nucleon axial-vector coupling constant in magnetar environments

Authors:C. A. Dominguez, Marcelo Loewe, Cristian Villavicencio, R. Zamora

Abstract: The nucleon axial-vector coupling constant $g_A$ is studied in the presence of an external magnetic field, and in dense nuclear environments, to emulate nuclear matter in magnetars. For this purpose we use QCD finite energy sum rules for two-current and three-current correlators, the former involving nucleon-nucleon correlators and the latter involving proton-axial-neutron currents. As a result, the axial-vector coupling constant decreases both with baryon density as well as with magnetic field. The axial-vector coupling evaluated with baryon density near the nuclear density $\rho_0$ leads to $g_A^*\approx 0.92$. In the presence of magnetic fields $g_A$ decreases in general, but $g_A^*$ does not show significant changes.

11.Assessing Lepton Flavor Universality Violations in Semileptonic Decays

Authors:Sonali Patnaik, Lopamudra Nayak, Rajeev Singh

Abstract: In light of recent measurements suggesting potential lepton flavor universality violations in semileptonic decays at LHCb and other collider experiments, this article offers a brief review of the theoretical basis of tree- and loop-level $B$-hadron decays, $b \to c l \nu_l$ and $b \to s l^+ l^-$, and the experimental conditions. We reassess global averages for $\mathcal{R}_{D(D^*)}$, $\mathcal{R}_{K(K^*)}$, $\mathcal{R}_{J/\psi}$, and $\mathcal{R}_{\eta_c}$ in semileptonic transitions and have also provided the results for $B_c$ decay channels within the relativistic independent quark model context. If LHC Run 2 data evaluation corroborates Run 1 measurements, the effect of statistical significance in each decay channel could reach 5\,$\sigma$. The confirmation of these measurements could soon represent the first notable observation of physics beyond the Standard Model, broadening our perspective of New Physics.

12.Semi-visible dark photon in a model with vector-like leptons for the $(g-2)_{e,μ}$ and $W$-boson mass anomalies

Authors:Waleed Abdallah, Mustafa Ashry, Junichiro Kawamura, Ahmad Moursy

Abstract: We propose a model realizes that a semi-visible dark photon which can contribute to the anomalous magnetic moment ($g-2$) of both electron and muon. In this model, the electron $g-2$ is deviated from the Standard Model (SM) prediction by the 1-loop diagrams involving the vector-like leptons, while that of muon is deviated due to a non-vanishing gauge kinetic mixing with photons. We also argue that the $W$-boson mass can be deviated from the SM prediction due to the vector-like lepton loops, so that the value obtained by the CDF II experiment can be explained. Thus, this model simultaneously explains the recent three anomalies in $g-2$ of electron and muon as well as the $W$-boson mass. The constraints on the $\mathcal{O}(1)~\mathrm{GeV}$ dark photon can be avoided because of the semi-invisible decay of the dark photon, $A^\prime \to 2 N \to 2\nu \,2\chi \to 2\nu \,4e$, where $N$ is a SM singlet vector-like neutrino and $\chi$ is a CP-even Higgs boson of the $U(1)^\prime$ gauge symmetry.

13.Boosting likelihood learning with event reweighting

Authors:Siyu Chen, Alfredo Glioti, Giuliano Panico, Andrea Wulzer

Abstract: Extracting maximal information from experimental data requires access to the likelihood function, which however is never directly available for complex experiments like those performed at high energy colliders. Theoretical predictions are obtained in this context by Monte Carlo events, which do furnish an accurate but abstract and implicit representation of the likelihood. Strategies based on statistical learning are currently being developed to infer the likelihood function explicitly by training a continuous-output classifier on Monte Carlo events. In this paper, we investigate the usage of Monte Carlo events that incorporate the dependence on the parameters of interest by reweighting. This enables more accurate likelihood learning with less training data and a more robust learning scheme that is more suited for automation and extensive deployment. We illustrate these advantages in the context of LHC precision probes of new Effective Field Theory interactions.

14.Correlating neutrino millicharge and muon $(g-2)$ in an abelian $L_μ-L_τ$ model

Authors:Ashutosh Kumar Alok, Neetu Raj Singh Chundawat, Arindam Mandal

Abstract: The inclusion of an additional $U(1)$ gauge symmetry is a common feature in many extensions of the Standard Model, revealing the intricate connections between particle physics and cosmology. The $L_{\mu} - L_{\tau}$ model stands as a prominent member of this distinguished family, characterized by its anomaly-free nature and resilience in the face of collider constraints. This framework provides a unique vantage point for investigating both the intriguing mystery of the muon $(g-2)$ anomaly and the puzzling issue of the Hubble tension. However, due to the presence of kinetic mixing between the photon and $Z'$ in this model, the neutrinos have the potential to acquire minuscule electric charges, often referred to as millicharges ($q_{\nu}$) which is directly related to the strength of the new gauge couplings. A crucial question emerges: how does the model's inclusion of millicharges, while adhering to the stringent constraints imposed by experimental observations, influence its inherent ability to address the muon $(g-2)$ anomaly and the Hubble tension? We find the current upper bounds on $q_{\nu}$ derived from experiments such as the beam dump, XENONnT and LUX-ZEPLIN experiments can impose strong constraints on the $U(1)_{L_{\mu} - L_{\tau}}$ coupling. Consequently, these constraints may limit the ability of the model to fully accommodate the current measurement of $(g-2)_{\mu}$ while having a relatively minor impact on the resolution of the Hubble tension.

15.$(g-2)_μ$ and Stau coannihilation : Dark Matter and Collider Analysis

Authors:Manimala Chakraborti, Sven Heinemeyer, Ipsita Saha

Abstract: Slepton coannihilation is one of the most promising scenarios that can bring the predicted Dark Matter (DM) abundance in the the Minimal Supersymmetric Standard Model (MSSM) into agreement with the experimental observation. In this scenario, the lightest supersymmetric particle (LSP), usually assumed to be the lightest neutralino, can serve as a Dark Matter (DM) candidate while the sleptons as the next-to-LSPs (NLSPs) lie close in mass. In our previous studies analyzing the electroweak (EW) sector of MSSM, a degeneracy between the three generations of sleptons was assumed for the sake of simplicity. In case of slepton coannihilation this directly links the smuons involved in the explanation for $(g-2)_\mu$ to the coannihilating NLSPs required to explain the DM content of the universe. On the other hand, in Grand Unified Theories such degeneracy do not hold, and often the lighter stau turns out to be the NLSP at the EW scale, with the smuons (and selectrons) somewhat heavier. In this paper we analyze a non-universal slepton mass scenario at the EW scale where the first two generations of sleptons are taken to be mass-degenerate and heavier than the staus, enforcing stau coannihilation. We analyze the parameter space of the MSSM in the light of a variety of experimental data namely, the DM relic density and direct detection (DD) limits, LHC data and especially, the discrepancy between the experimental result for $(g-2)_\mu$, and its Standard Model (SM) prediction. We find an upper limit on the LSP and NLSP masses of about ~ 550 GeV. In contrast to the scenario with full degeneracy among the three families of sleptons, the upper limit on the light smuon/selectron mass moves up by ~ 200 GeV. We analyze the DD prospects as well as the physics potential of the HL-LHC and a future high-energy $e^+ e^-$ collider to investigate this scenario further.

16.Perturbative contributions to $Δα^{(5)}(M^2_Z)$

Authors:Jens Erler, Rodolfo Ferro-Hernandez

Abstract: We compute a theoretically driven prediction for the hadronic contribution to the electromagnetic running coupling at the $Z$ scale using lattice QCD and state-of-the-art perturbative QCD. We obtain$$\Delta\alpha^{(5)}(M^2_Z)=\left[279.5\pm0.9\pm0.59\right]\times10^{-4}\quad\quad\,\,\,\,\,\,(\mathrm{Mainz \,\,\,Collaboration})$$$$\Delta\alpha^{(5)}(M^2_Z)=\left[278.42\pm0.22\pm0.59\right]\times10^{-4}\,\,\,\,\,\,\,\,\quad(\mathrm{ BMW \,\,\,Collaboration}),$$ where the first error is the quoted lattice uncertainty. The second is due to perturbative QCD, and is dominated by the parametric uncertainty on $\hat{\alpha}_s$, which is based on a rather conservative error. Using instead the PDG average, we find a total error on $\Delta\alpha^{(5)}(M^2_Z)$ of $0.4\times10^{-4}$. Furthermore, with a particular emphasis on the charm quark contributions, we also update $\Delta\alpha^{(5)}(M^2_Z)$ when low-energy cross-section data is used as an input, obtaining $\Delta\alpha^{(5)}(M^2_Z) = \left[276.29 \pm 0.38 \pm 0.62\right] \times 10^{-4}$. The difference between lattice QCD and cross-section-driven results reflects the known tension between both methods in the computation of the anomalous magnetic moment of the muon. Our results are expressed in a way that will allow straightforward modifications and an easy implementation in electroweak global fits.

17."QGP Signatures" Revisited

Authors:John W. Harris, Berndt Müller

Abstract: We revisit the graphic table of QCD signatures in our 1996 Annual Reviews article "The Search for the Quark-Gluon Plasma" and assess the progress that has been made since its publication towards providing quantitative evidence for the formation of a quark-gluon plasma in relativistic heavy-ion collisions and its characteristic properties.

1.Gravitational form factors of the proton from near-threshold vector meson photoproduction

Authors:Xiao-Yun Wang, Fancong Zeng

Abstract: We embark on a systematical analysis of the quark and gluon gravitational form factors (GFFs) of the proton, by connecting energy-momentum tensor and the near-threshold vector meson photoproduction (NTVMP). Concretely, the quark contributions of GFFs are determined unprecedentedly by global fitting the cross section of the lightest vector meson $\rho^0$ photoproduction. Combined with the gluon GFFs achieved from heavy quarkonium $J/\psi$ photoproduction data, the complete GFFs are obtained and compared with the deeply virtual Compton scattering experimental results and LQCD determinations. The profound implications of this finding cannot be overstated, as it opens new avenues for obtaining comprehensive information on GFFs. Naturally, this work is not only an important basis for delving the proton enigmatic properties, % unraveling the secrets of the proton internal nature but also have significance theoretical guiding for future JLab and EICs experimental measurements.

2.UPCs as probes of partonic structure -- exclusive and inclusive processes

Authors:V. Guzey Jyvaskyla U. and Helsinki U.

Abstract: Ultraperipheral collisions (UPCs) at the LHC and RHIC provide important new information on the partonic structure of the proton and nuclei and small-$x$ dynamics in QCD. We review phenomenological applications of the collinear factorization at leading and next-to-leading orders of perturbative QCD and the dipole model to coherent and incoherent $J/\psi$ photoproduction in Pb-Pb UPCs at the LHC emphasizing the strong leading twist gluon nuclear shadowing, the role of quark-antiquark-gluon dipoles, and a possible onset the gluon saturation in nuclei. We also discuss inclusive and diffractive dijet photoproduction in UPCs, which give complementary constraints on nuclear parton distributions and the pattern of factorization breaking in diffraction.

3.Meson cloud contributions to the Dalitz decays of decuplet to octet baryons

Authors:G. Ramalho, K. Tsushima

Abstract: We study the role of the meson cloud on the electromagnetic transitions from decuplet ($B'$) to octet ($B$) baryons in terms of the squared four-momentum transfer $q^2$. In the quark model framework, the meson cloud dressing of the quark cores gives important contributions to the $\gamma^\ast N \to \Delta(1232)$ transition form factors. In the present work, we estimate the meson cloud contributions of all decuplet to octet baryon transitions ($\gamma^\ast B \to B'$ or $B' \to \gamma^\ast B$). Models that combine valence quark effects with pion and kaon cloud dressing provide a fair description of the radiative decays of decuplet to octet baryons, namely the $\Sigma^0(1385) \to \gamma \Lambda (1116)$ and $\Sigma^+(1385) \to \gamma \Sigma^+ (1193)$ decays. Previous studies indicated the relevance of the pion cloud effects on the $B^\prime \to \gamma^\ast B$ transition, but also suggested that the kaon cloud contributions may be important in the timelike region. We combine then the contributions of the bare core, estimated by a covariant quark model, with $q^2$-dependent contributions of pion and kaon clouds. We use the framework to calculate the Dalitz decay rates and the Dalitz decay widths of decuplet baryons in octet baryons with di-electrons ($B' \to e^+ e^- B$) or di-muons ($B' \to \mu^+ \mu^- B$). We conclude, based on the magnitude of our results, that most estimates of the $B' \to e^+ e^- B$ Dalitz decay widths may be tested at HADES and PANDA (GSI) in a near future. We discuss also the possibility of measuring the $\Delta (1232) \to \mu^+ \mu^- N$ and $\Sigma^0 (1385) \to \mu^+ \mu^- \Lambda (1116)$ decay widths in some facilities, based on the estimated branching ratios.

4.Properties of Heavy Higgs Bosons and Dark Matter under Current Experimental Limits in the $μ$NMSSM

Authors:Zhaoxia Heng, Xingjuan Li, Liangliang Shang

Abstract: Searches for new particles beyond the Standard Model (SM) are an important task for the Large Hadron Collider (LHC). In this paper, we investigate the properties of the heavy non-SM Higgs bosons in the $\mu$-term extended Next-to-Minimal Supersymmetric Standard Model ($\mu$NMSSM). We scan the parameter space of the $\mu$NMSSM considering the basic constraints from Higgs data, dark matter (DM) relic density, and LHC searches for sparticles. And we also consider the constraints from the LZ2022 experiment and the muon anomaly constraint at 2$\sigma$ level. We find that the LZ2022 experiment has a strict constraint on the parameter space of the $\mu$NMSSM, and the limits from the DM-nucleon spin-independent (SI) and spin-dependent (SD) cross-sections are complementary. Then we discuss the exotic decay modes of heavy Higgs bosons decaying into SM-like Higgs boson. We find that for doublet-dominated Higgs $h_3$ and $A_2$, the main exotic decay channels are $h_3\rightarrow Z A_1$, $h_3\rightarrow h_1 h_2$, $A_2\rightarrow A_1 h_1$ and $A_2\rightarrow Z h_2$, and the branching ratio can reach to about 23$\%$, 10$\%$, 35$\%$ and 10$\%$ respectively. At the 13 TeV LHC, the production cross-section of $ggF\rightarrow h_3\rightarrow h_1 h_2$ and $ggF\rightarrow A_2\rightarrow A_1 h_1$ can reach to about $10^{-11}$pb and $10^{-10}$pb, respectively.

5.Discovery Prospects for Electron and Neutron Electric Dipole Moments in the General Two Higgs Doublet Model

Authors:Wei-Shu Hou, Girish Kumar, Sven Teunissen

Abstract: Baryon asymmetry of the Universe offers one of the strongest hints for physics Beyond the Standard Model (BSM). Remarkably, in the general two Higgs Doublet Model (g2HDM) that possesses a second set of Yukawa matrices, one can have electroweak baryogenesis (EWBG) while the electron electric dipole moment (eEDM) is evaded by a natural flavor tuning that echoes SM. We show that eEDM may first emerge around $10^{-30}\,e$ cm or so, followed by neutron EDM (nEDM) down to $10^{-27}\,e$ cm. We illustrate a cancellation mechanism for nEDM itself, which in turn can be probed when a facility capable of pushing down to $10^{-28}\,e$ cm becomes available.

6.Lévy $α$-stable model for the non-exponential low-$|t|$ proton-proton differential cross section

Authors:T. Csörgő, S. Hegyi, I. Szanyi

Abstract: It is known that the Real Extended Bialas-Bzdak (ReBB) model describes the proton-proton ($pp$) and proton-antiproton ($p\bar p$) differential cross-section data in a statistically non-excludible way,\linebreak i.e., with a confidence level greater than or equal to 0.1\% in the center of mass energy range \linebreak 546 GeV $\leq\sqrt{s}\leq$ 8 TeV and in the squared four-momentum transfer range 0.37 GeV$^2$ $\leq -t\leq$ 1.2 GeV$^2$. Considering, instead of Gaussian, a more general L\'evy $\alpha$-stable shape for the parton distributions of the constituent quark and diquark inside the proton and for the relative separation between them, a generalized description of data is obtained, where the ReBB model corresponds to the $\alpha =$ 2 special case. Extending the model to $\alpha <$ 2, we conjecture that the validity of the model can be extended to a wider kinematic range, in particular, to lower values of the four-momentum transfer $-t$. We present the formal L\'evy $\alpha$-stable generalization of the Bialas-Bzdak model and show that a simplified version of this model can be successfully fitted, with $\alpha<$ 2, to the non-exponential, low $-t$ differential cross-section data of elastic proton-proton scattering at $\sqrt{s} =$ 8 TeV.

7.Two-loop Vertices with Vacuum Polarization Insertion

Authors:Taushif Ahmed, Giulio Crisanti, Federico Gasparotto, Syed Mehedi Hasan, Pierpaolo Mastrolia

Abstract: We present the analytic evaluation of the second-order corrections to the massive form factors, due to two-loop vertex diagrams with a vacuum polarization insertion, with exact dependence on the external and internal fermion masses, and on the squared momentum transfer. We consider vector, axial-vector, scalar and pseudoscalar interactions between the external fermion and the external field. After renormalization, the finite expressions of the form factors are expressed in terms of polylogarithms up to weight three.

8.Search for a Non-Relativistic Boson in Two-Body Antimuon Decay

Authors:J. I. Collar, P. S. Cooper, C. M. Lewis

Abstract: We demonstrate the feasibility of probing the charged lepton flavor violating decay $\mu^{+}\!\!\rightarrow \!e^{+} X^{0}$ for the presence of a slow-moving neutral boson $X^{0}$ capable of undergoing gravitational binding to large structures, and as such able to participate in some cosmological scenarios. A short exposure to surface antimuons from beamline M20 at TRIUMF generates a branching ratio limit of $\lesssim 10^{-5}$. This is comparable or better than previous searches for this channel, although in a thus-far unexplored region of $X^{0}$ phase space very close to the kinematic limit of the decay. The future improved sensitivity of the method using a customized p-type point contact germanium detector is described.

9.`Maximal conformality' is nonsense

Authors:P. M. Stevenson

Abstract: The so-called "principle of maximal conformality" is nonsense and does nothing to resolve the renormalization-scheme-dependence problem. Some essential facts about that problem are summarized. It is stressed that RG invariance is a symmetry and that any viable method for resolving the scheme-dependence problem should be formulatable in terms of the invariants of that symmetry.

10.From Dirac to Majorana: the Cosmic Neutrino Background capture rate in the minimally extended Standard Model

Authors:Yuber F. Perez-Gonzalez, Manibrata Sen

Abstract: We investigate the capture rate of the cosmic neutrino background on tritium within the Standard Model, extended to incorporate three right-handed singlet neutrinos with explicit lepton-number violation. We consider a scenario where the $6 \times 6$ neutrino mixing matrix factorizes into three independent $2 \times 2$ pairs and analyze the states produced from weak interactions just before neutrino decoupling. Taking into account the unrestricted Majorana mass scale associated with lepton number violation, spanning from the Grand Unification scale to Planck-suppressed values, we observe a gradual transition in the capture rate from a purely Majorana neutrino to a purely (pseudo) Dirac neutrino. We demonstrate that the capture rate is modified if the lightest active neutrino is relativistic, and this can be used to constrain the tiniest value of mass-squared difference $\sim 10^{-35}\,{\rm eV}^2$, between the active-sterile pair, probed so far. Consequently, the cosmic neutrino capture rate could become a promising probe for discerning the underlying mechanism responsible for generating neutrino masses.

11.Expected sensitivity on the anomalous quartic neutral gauge couplings in $γγ$ collisions at the CLIC

Authors:E. Gurkanli, M. Köksal, A. Gutiérrez-Rodríguez, M. A. Hernández-Ruíz, V. Ari

Abstract: The presence of multi-boson self-interactions is implied by the non-Abelian gauge structure of the Standard Model (SM). Precise measurements of these interactions allow not only testing the nature of the SM but also new physics contribution arising from the beyond SM. The investigation of these interactions can be approached in a model-independent manner using an effective theory approach, which forms the main motivation of this study. In this paper, we examine the anomalous neutral quartic gauge couplings through the process $\gamma \gamma \rightarrow Z Z$ at the Compact Linear Collider (CLIC) with the center-of-mass energy of $\sqrt{s}=3$ TeV, integrated luminosities of ${\cal L}=5$ $\rm ab^{-1}$. The anomalous neutral quartic gauge couplings is implemented into FeynRules to generate a UFO module inserted into Madgraph to generate both background and signal events. These events are then passed through Pythia 8 for parton showering and Delphes to include realistic detector effects. We obtain that the sensitivities on the anomalous quartic neutral gauge couplings with $95\%$ Confidence Level are given as: $f_{T0}/\Lambda^{4}=[-1.06; 1.08]\times 10^{-3}$ ${\rm TeV^{-4}}$, $f_{T1}/\Lambda^{4}=[-1.06; 1.08]\times 10^{-3}$ ${\rm TeV^{-4}}$,$f_{T2}/\Lambda^{4}=[-1.06; 1.08]\times 10^{-3}$ ${\rm TeV^{-4}}$,$f_{T0}/\Lambda^{4}=[-1.06; 1.08]\times 10^{-3}$ ${\rm TeV^{-4}}$, $f_{T5}/\Lambda^{4}=[-4.08; 4.08]\times 10^{-4}$ ${\rm TeV^{-4}}$ and $f_{T8}/\Lambda^{4}=[-1.10; 1.10]\times10^{-4}$ ${\rm TeV^{-4}}$. Our results on the anomalous quartic neutral gauge couplings are set more stringent sensitivity with respect to the recent experimental limits.

12.Z $\to$ 3X decay width from dark matter Standard Model extension

Authors:D. O. R. Azevedo, M. L. Bispo, O. M. Del Cima, J. A. Helayël-Neto

Abstract: We propose a Born-Infeld contribution to the $U(1)_{B-L}$ extension of the Standard Model to explain the anomalous decay of beryllium by the X17 neutral boson, its possible connections to dark matter and the observed MeV gamma-ray bursts. The decay width of the $Z^0$ decay into 3$X$ process is computed based on NA64 experiment data.

13.Flavour constraints on light spin-1 bosons within a chiral Lagrangian approach

Authors:Luca Di Luzio, Gabriele Levati, Paride Paradisi, Xavier Ponce Díaz

Abstract: We discuss the construction of the chiral Lagrangian for a light spin-1 boson, here denoted as $X$, featuring both vector and axial-vector couplings to light $u,d,s$ quarks. Focusing on $\Delta S = 1$ transitions, we show that there are model-independent tree-level contributions to $K^\pm \to \pi^\pm X$, sourced by Standard Model charged currents, which receive an $m^2_K / m_X^2$ enhancement from the emission of a longitudinally polarized $X$. This flavour observable sets the strongest to date model-independent bound on the diagonal axial-vector couplings of $X$ to $u,d,s$ quarks for $m_X < m_K - m_\pi$, superseding the bounds arising from beam-dump and collider searches.

14.Investigation of CP-even Higgs bosons decays $H \rightarrow μτ$ within constraints of $l_a \rightarrow l_b γ$ in a 3-3-1 model with inverse seesaw neutrinos

Authors:H. V. Quyet, T. T. Hieu, N. T. Tham, N. T. T. Hang, H. T. Hung

Abstract: In a 3-3-1 model with inverse seesaw neutrinos, we use a simple form of Higgs potential to give four CP-even Higgs bosons ($H \equiv h^0_1,h^0_2,h^0_3,h^0_4$). We investigate $H \rightarrow \mu \tau$ decays in the parameter space regions satisfying the experimental limits of $l_a \rightarrow l_b \gamma$ with running parameters being the mass of the charged Higgs boson ($m_{H_1^\pm}$) and the mixing matrix of the heavy neutrinos ($M_R$). We show that there exist regions of parameter space where all partial widths $\Gamma (H \rightarrow \mu \tau)$ are less than the current experimental limit ($4.1 \times 10^{-6} GeV$). Analyzing the contributing components to $\Gamma (H \rightarrow \mu \tau)$, we also compare the mass of the SM-like Higgs boson with the corresponding ones of the other CP-even Higgs bosons in this model.

15.A minimal model of fermion FIMP dark matter

Authors:Carlos E. Yaguna, Óscar Zapata

Abstract: We investigate a simple extension of the standard model (SM) in which the dark matter consists of a feebly interacting fermion (FIMP), charged under a new $Z_4$ symmetry, that is produced in the early Universe by the freeze-in mechanism. The only other new particle included in the model is a singlet scalar, also charged under the $Z_4$, which couples to the fermion via Yukawa interactions and to the SM Higgs. The model is truly minimal, as it admits just five free parameters: two masses and three dimensionless couplings. Depending on their values, the freeze-in mechanism can be realized in different ways, each characterized by its own production processes. For all of them, we numerically study the relic density as a function of the free parameters of the model and determine the regions consistent with the dark matter constraint. Our results show that this scenario is viable over a wide range of couplings and dark matter masses. This model, therefore, not only offers a novel solution to the dark matter problem, but it also provides a minimal realization of freeze-in for fermion dark matter.

1.The ${\cal O}(α_t+α_λ+α_κ)^2$ Correction to the $ρ$ Parameter and its Effect on the W Boson Mass Calculation in the Complex NMSSM

Authors:Thi Nhung Dao, Martin Gabelmann, M. Margarete Mühlleitner

Abstract: We present the prediction of the electroweak $\rho$ parameter and the $W$ boson mass in the CP-violating Next-to-Minimal Supersymmetric extension of the Standard Model (NMSSM) at the two-loop order. The $\rho$ parameter is calculated at the full one-loop and leading and sub-leading two-loop order $\mathcal{O}(\alpha + \alpha_t\alpha_s + \left(\alpha_t+\alpha_\lambda+\alpha_\kappa\right)^2)$. The new $\Delta \rho$ prediction is incorporated into a prediction of $M_W$ via a full supersymmetric (SUSY) one-loop calculation of $\Delta r$. Furthermore, we include all known state-of-the-art SM higher-order corrections to $\Delta r$. By comparing results for $\Delta \rho$ obtained using on-shell (OS) and $\overline{\mathrm{DR}}$ renormalization conditions in the top/stop sector, we find that the scheme uncertainty is reduced at one-loop order by 55%, at two-loop $\mathcal{O}(\alpha_s\alpha_t)$ by 22%, and at two-loop $\mathcal{O}(\alpha_t+\alpha_\kappa+\alpha_\lambda)^2$ by 16%, respectively. The influence of the two-loop results on the $M_W$ mass prediction is found to be sub-leading. The new calculation is made public in the computer program $\mathrm{\tt NMSSMCALC}$. We perform an extensive comparison in the $W$-mass, Higgs boson mass and the muon anomalous magnetic moment prediction between our calculation and three other publicly available tools and find very good agreement provided that the input parameters and renormalization scales are treated in the same way. Finally, we study the impact of the CP-violating phases on the $W$-mass prediction which is found to be smaller than the overall size of the SUSY corrections.

2.Intermediate Charge-Breaking Phases and Symmetry Non-Restoration in the 2-Higgs-Doublet Model

Authors:Mayumi Aoki, Lisa Biermann, Christoph Borschensky, Igor P. Ivanov, Margarete Mühlleitner, Hiroto Shibuya

Abstract: The Higgs potentials of extended Higgs sectors exhibit a complex and interesting vacuum structure. When travelling back in time, i.e. going to higher temperatures, the structure may change and exhibit interesting phase patterns and sequences of phases related to the respective minima of the potential. The investigation of the vacuum structure can give us indirect insights in beyond-Standard-Model physics and the evolution of the Universe. In this paper, we investigate the possibility of an intermediate charge-breaking (CB) phase in the 2-Higgs-Doublet Model (2HDM) type I. The existence has been reported previously by using a simple potential setup. We here confirm that the intermediate CB phase can still exist when using the one-loop corrected effective potential including thermal masses. We discuss its features and the relation with SU(2) symmetry (non-)restoration as well as its consistency with the current experimental data. Lastly, we show for some selected benchmark points the rich and interesting phase patterns and sequences that the 2HDM can undergo during its evolution from the early Universe to today's electroweak vacuum.

3.Puzzles in the hadronic contributions to the muon anomalous magnetic moment

Authors:Gilberto Colangelo, Martin Hoferichter, Peter Stoffer

Abstract: We summarize recent developments in the Standard-Model evaluation of the anomalous magnetic moment of the muon $a_\mu$, both in the hadronic-light-by-light and hadronic-vacuum-polarization contributions. The current situation for the latter is puzzling as we are confronted with multiple discrepancies that are not yet understood. We present updated fits of a dispersive representation of the pion vector form factor to the new CMD-3 data set and quantify the tensions with the other high-statistics $e^+e^-\to\pi^+\pi^-$ experiments in the contribution to $a_\mu$ in the energy range up to 1 GeV, as well as in the corresponding contribution to the intermediate Euclidean window.

4.Hadronic vacuum polarization: comparing lattice QCD and data-driven results in systematically improvable ways

Authors:Michel Davier, Zoltan Fodor, Antoine Gerardin, Laurent Lellouch, Bogdan Malaescu, Finn M. Stokes, Kalman K. Szabo, Balint C. Toth, Lukas Varnhorst, Zhiqing Zhang

Abstract: The precision with which hadronic vacuum polarization (HVP) is obtained determines how accurately important observables, such as the muon anomalous magnetic moment, a_\mu, or the low-energy running of the electromagnetic coupling, \alpha, are predicted. The two most precise approaches for determining HVP are: dispersive relations combined with e+e- to hadrons cross-section data, and lattice QCD. However, the results obtained in these two approaches display significant tensions, whose origins are not understood. Here we present a framework that sheds light on this issue and, if the two approaches can be reconciled, allows them to be combined. Via this framework, we test the hypothesis that the tensions can be explained by modifying the R-ratio in different intervals of center-of-mass energy sqrt(s). As ingredients, we consider observables that have been precisely determined in both approaches. These are the leading hadronic contributions to a_\mu, to the so-called intermediate window observable and to the running of \alpha between spacelike virtualities 1GeV^2 and 10GeV^2 (for which only a preliminary lattice result exists). Our tests take into account all uncertainties and correlations, as well as uncertainties on uncertainties in the lattice results. Among our findings, the most striking is that results obtained in the two approaches can be made to agree for all three observables by modifying the \rho peak in the experimental spectrum. In particular, we find that this requires a common ~5\% increase in the contributions of the peak to each of the three observables. This finding is robust against the presence or absence of one of the constraining observables. However, such an increase is much larger than the uncertainties on the measured R-ratio. We also discuss a variety of generalizations of the methods used here, as well as the limits in the information that can be extracted...

5.Kinematic twist-three contributions to pseudo- and quasi-GPDs

Authors:V. M. Braun

Abstract: We present explicit expressions for the tree-level ``kinematic'' twist-three contributions to the nucleon matrix elements of gauge-invariant nonlocal quark-antiquark operators which can be used in lattice calculations of generalized parton distributions (GPDs). These contributions in particular restore the translation invariance of the results up to higher twist four. The calculated twist-three corrections are logarithmically enhanced as compared to the leading twist, and are discontinuous at the kinematic points $x=\pm\xi$.

6.Double-gluon charmonium hybrid states with various (exotic) quantum numbers

Authors:Niu Su, Hua-Xing Chen, Wei Chen, Shi-Lin Zhu

Abstract: We study the double-gluon charmonium hybrid states with various quantum numbers, each of which is composed of one valence charm quark and one valence charm antiquark as well as two valence gluons. We concentrate on the exotic quantum numbers $J^{PC} =0^{--}/0^{+-}/1^{-+}/2^{+-}/3^{-+}$ that the conventional $\bar q q$ mesons can not reach. We apply the QCD sum rule method to calculate their masses to be $7.28^{+0.38}_{-0.43}$ GeV, $5.19^{+0.36}_{-0.46}$ GeV, $5.46^{+0.41}_{-0.62}$ GeV, $4.48^{+0.25}_{-0.31}$ GeV, and $5.54^{+0.35}_{-0.43}$ GeV, respectively. We study their possible decay patterns and propose to search for the $J^{PC}=2^{+-}/3^{-+}$ states in the $D^*\bar D^{(*)}/D^{*}_s \bar D^{(*)}_s/\Sigma_c^* \bar \Sigma_c^{(*)}/\Xi_c^* \bar \Xi_c^{(\prime,*)}$ channels. Experimental investigations on these states and decay channels can be useful in classifying the nature of the hybrid state, thus serving as a direct test of QCD in the low energy sector.

7.Looking for an axion in a haystack of muons

Authors:A. Gurgone on behalf of the McMule team

Abstract: The search for axion-like particles $X$ in muon decays is an excellent opportunity for the MEG II and Mu3e experiments to extend their horizons beyond $\mu^+ \to e^+ \gamma$ and $\mu^+ \to e^+ e^- e^+$. A suitable process for both experiments is the two-body decay $\mu^+ \to e^+ X$, whose only signature is a monochromatic peak close to the kinematic endpoint of the positron energy spectrum of the $\mu^+ \to e^+ \nu_e \bar\nu_\mu$ background. The hunt for such an elusive signal in a vast amount of irreducible background requires extremely accurate theoretical predictions to be implemented in a Monte Carlo event generator. This work presents a new state-of-the-art computation of $\mu^+ \to e^+ \nu_e \bar\nu_\mu$ for polarised muons, accomplished with the McMule framework. The calculation includes next-to-next-leading order QED corrections and logarithmically enhanced terms at even higher orders. The results are also used to estimate the sensitivity of both experiments on the branching ratio of $\mu^+ \to e^+ X$, in order to evaluate the impact of the theoretical error.

8.New determination of $|V_{ub}/V_{cb}|$ from $B_s^0\to \lbrace K^-, D_s^- \rbrace μ^+ν$

Authors:Carolina Bolognani, Danny van Dyk, K. Keri Vos

Abstract: We update the full set of $\bar{B}_s\rightarrow K$ form factors using light-cone sum rules with an on-shell kaon. Our approach determines the relevant sum rule parameters -- the duality thresholds -- from a Bayesian fit for the first time. Using a modified version of the Boyd-Grinstein-Lebed parametrisation, we combine our sum rule results at low momentum transfer $q^2$ with more precise lattice QCD results at large $q^2$. We obtain a consistent description of the form factors in the full $q^2$ range. Applying these results to a recent LHCb measurement of branching ratios for the decays $B_s^0 \to \lbrace K^-, D_s^-\rbrace \mu^+\nu_\mu$, we determine the ratio of Cabibbo-Kobayashi-Maskawa elements $$ \notag \left|\frac{V_{ub}}{V_{cb}}\right|_{q^2<7\; \textrm{GeV}^2} = 0.0681\pm 0.0040 \quad \text{and} \quad \left|\frac{V_{ub}}{V_{cb}}\right|_{q^2>7 \;\textrm{GeV}^2} = 0.0801\pm 0.0047 \ , $$ which are mutually compatible at the $1.9\sigma$ level. We further comment on the sensitivity to Beyond the Standard Model effects through measurements of the shape of $B_s^0 \to K^- \mu^+\nu_\mu$ decays, in light of recent limits on such effects from other exclusive $b\to u\ell\nu$ processes.

9.Heavy quarkonia in QGP medium in an arbitrary magnetic field

Authors:Jobin Sebastian, Lata Thakur, Hiranmaya Mishra, Najmul Haque

Abstract: We compute the heavy quarkonium complex potential in an arbitrary magnetic field strength generated in the relativistic heavy-ion collision. First, the one-loop gluon polarization tensor is obtained in the presence of an external, constant, and homogeneous magnetic field using the Schwinger proper time formalism in Euclidean space. The gluon propagator is computed from the gluon polarization tensor, and it is used to calculate the dielectric permittivity in the presence of the magnetic field in the static limit. The modified dielectric permittivity is then used to compute the heavy quarkonium complex potential. We find that the heavy quarkonium complex potential is anisotropic in nature, which depends on the angle between the quark-antiquark ($Q\bar{Q}$) dipole axis and the direction of the magnetic field. We discuss the effect of the magnetic field strength and the angular orientation of the dipole on the heavy quarkonium potential. We discuss how the magnetic field influences the thermal widths of quarkonium states. Further, we also discuss the limitation of the strong-field approximation as done in literature in the light of heavy-ion observables, as the effect of the magnetic field is very nominal to the quarkonium potential.

10.Fermion mass, Axion dark matter, and Leptogenesis in SO(10) GUT

Authors:Ajay Kaladharan, Shaikh Saad

Abstract: SO(10) grand unified theory with minimum parameters in the Yukawa sector employs the Peccei-Quinn symmetry that solves the strong CP problem. Such an economical Yukawa sector is highly appealing and has been extensively studied in the literature. However, when the running of the renormalization group equations of the Yukawa couplings are considered, this scenario shows somewhat tension with the observed fermion masses and mixing. In this work, we propose an extension of the minimal framework that alleviates this tension by introducing only a few new parameters. The proposed model consists of a fermion in the fundamental and a scalar in the spinorial representations. While the latter is needed to implement the Peccei-Quinn symmetry successfully, the presence of both is essential in obtaining an excellent fit to the fermion mass spectrum. In our model, axions serve the role of dark matter, and the out-of-equilibrium decays of the right-handed neutrinos successfully generate the matter-antimatter symmetry of the Universe.

11.Nucleon Resonance Masses from QCD Sum Rules

Authors:Nasrallah F. Nasrallah, Karl Schilcher

Abstract: Abstract We present a calculation of the masses of the established nucleon recurrence N+(1440), N-(1535), N-(1650), N+(1710), N+(1880), N-(1895), N+(2100) using a new method of finite energy QCD sum rules. The method is based on the idea of choosing a suitable integration kernel which minimizes the occurring integral over the cut in the complex energy (squared) plane. We obtain remarkably stable results in a wide range R, where R is the radius of the integration contour. The sum rule predictions agree with the experimental values within the expected accuracy showing that QCD describes single nucleon resonances

1.Interpretation of near-threshold peaks using the method of independent S-matrix poles

Authors:Leonarc Michelle Santos, Denny Lane B. Sombillo

Abstract: We proposed a model-independent analysis of near-threshold enhancements using independent S-matrix poles. In this formulation, we constructed a Jost function with controllable zeros to ensure that no poles are generated on the physical Riemann sheet. We show that there is a possibility of misinterpreting the observed near-threshold signals if one utilized a limited parametrization and restrict the analysis to only one element of the S-matrix. Specifically, there is a possibility of the emergence of ambiguous pair of poles which are singularities of the full S-matrix but may not manifest in one of its elements. We apply our method to the analysis of $P_\psi^N(4312)^+$ and found that the compact pentaquark interpretation cannot be ruled out.

2.Cumulative activity of inelastic events under hadron collisions

Authors:S. M. Troshin, N. E. Tyurin

Abstract: We introduce the notion of cumulative activity for inelastic events generated under hadron collisions, discuss its energy dependence and connection with the reflective scattering mode. These issues are relevant for enlightening the asymptotic dynamics in view of the LHC measurements.

3.Probing the high-energy dynamics of QCD: selected theoretical and phenomenological studies

Authors:Michael Fucilla

Abstract: The center-of-mass energies available at modern accelerators, such as the Large Hadron Collider (LHC), and at forthcoming generation accelerators, such as the Electron-Ion Collider (EIC), offer us a unique opportunity to investigate hadronic matter under the most extreme conditions ever reached. In particular, we can access the Regge-Gribov regime of QCD, described by the Balitsky-Fadin-Kuraev-Lipatov (BFKL) approach along with its non-linear generalizations (the set of B-JIMWLK equations). The aim of these approaches is to resum large-energy logarithmic corrections which spoil the convergence of perturbative series at high-energy. The aforementioned approaches are theoretically developed both in the leading (LL) and the next-to-leading (NLL) approximation, but precise full NLL predictions still remains an open challenge. Furthermore, extending BFKL beyond the NLL approximation has been an open problem for more than twenty years. We face the task of hunting precision in this field from different perspectives. In particular, within the BFKL approach, we calculate the next-to-leading order (NLO) impact factor for the Higgs boson production. This is the necessary ingredient to study the inclusive forward emissions of a Higgs boson in association with a backward identified jet. Moreover, by using already known NLO impact factors, we propose a series of new semi-hard reactions that can be used to investigate BFKL dynamics at the LHC within NLL accuracy. We consider also the problem of extending BFKL beyond the NLL approximation and compute one of the ingredients entering the BFKL kernel at the next-to-NLL (NNLL) accuracy. Finally, in the saturation (non-linear) framework, we calculate the diffractive double hadron photo- or electroproduction cross sections with full NLL accuracy, useful to detect saturation effects, at both the future EIC or already at LHC (via Ultra Peripheral Collisions).

4.Dalitz decays $D_{sJ}^{(*)} \to D_s^{(*)} \ell^+ \ell^- $

Authors:Pietro Colangelo, Fulvia De Fazio, Francesco Loparco, Nicola Losacco

Abstract: The Dalitz decays of the positive parity $D_{sJ}^{(*)}$ charmed mesons, $D_{sJ}^{(*)} \to D_s^{(*)} \ell^+ \ell^-$ with $J=0,1,2$ and $\ell=e, \mu$, are important processes to investigate the nature of the $D_{sJ}^{(*)}$ states. We analyze the full set of decays, considering the four lightest $D_{sJ}^{(*)}$ mesons as belonging to the heavy quark spin doublets $\displaystyle s_\ell^P=\frac{1}{2}^+$ and $\displaystyle \frac{3}{2}^+$, with $s_\ell^P$ the spin-parity of the light degrees of freedom in mesons. The description implies relations among the observables in various modes. We study the decay distributions in the dilepton invariant mass squared and the distributions in the angle between the charged lepton momentum and the momentum of the produced meson, which are expressed in terms of universal form factors and of effective strong couplings. Such measurements are feasible at the present facilities.

5.Investigation of spin-dependent dark matter in mono-photon production at high-energy colliders

Authors:G. Gil da Silveira, M. S. Mateus Jr

Abstract: Many theories about dark matter have emerged due to its strong theoretical appeal in explaining astrophysical phenomena. However, experimental and theoretical particle physics have yet not provided evidence that dark matter is part of the observable Universe. Our work aims to investigate the interaction between Standard Model (SM) fermions and different species of dark matter (DM) particles in high-energy collisions through interaction of a new massive vector mediator, Z'. The production of scalar and fermion DM pairs via fermion annihilation into the new vector boson is investigated near a resonance, where a SM signal from hard photon emission is considered as initial state radiation, namely a mono-photon production. Values of coupling constants between the DM and the SM particles are mapped in contrast to the Planck satellite data for thermal relic density DM computed in the correct framework for the relic density near a resonance, where a weaker suppression of the relic density is expected. We show for the CLIC and LHC kinematic regimes that certain mass ranges and coupling constants of these DM particles are in agreement with the expected relic density near a resonance and are not excluded by collider and astrophysical limits.

6.Sensitivity of octant of $θ_{23}$, CP violation and mass hierarchy in NO$ν$A with multinucleon and detector effects

Authors:Paramita Deka, Kalpana Bora

Abstract: In this work, we investigate how multinucleon enhancement and RPA (Random Phase Approximation) suppression can affect the measurement of three unknown neutrino oscillation parameters - the CP-violating phase $\delta_{CP}$, the octant of the atmospheric mixing angle $\theta_{23}$, and the determination of the mass hierarchy, in the appearance channel of the NO$\nu$A experiment. We include the presence of the detector effect as well in the analysis, which is crucial for capturing realistic experimental scenarios. It is found that the analysis using our comprehensive model (QE(+RPA)+2p2h) exhibits significantly enhanced sensitivity compared to the pure QE interaction process, in all the cases. Also, the higher octant of $\theta_{23}$, the lower half plane of $\delta_{CP}$, and the normal mass hierarchy (HO-LHP-NH) exhibit improved sensitivity, enabling a more precise determination of the corresponding parameters. Furthermore, it is also noted that improving the performance of the detector also improves the results. Thus, including multinucleon effects and improving detector efficiency have the potential to enhance the capabilities of the NO$\nu$A (and other long baseline) experiment in conducting precise parameter studies.

7.Quantum Gravity Effects on Dark Matter and Gravitational Waves

Authors:Stephen F. King, Rishav Roshan, Xin Wang, Graham White, Masahito Yamazaki

Abstract: We explore how quantum gravity effects, manifested through the breaking of discrete symmetry responsible for both Dark Matter and Domain Walls, can have observational effects through CMB observations and gravitational waves. To illustrate the idea we consider a simple model with two scalar fields and two $\mathcal{Z}_2$ symmetries, one being responsible for Dark Matter stability, and the other spontaneously broken and responsible for Domain Walls, where both symmetries are assumed to be explicitly broken by quantum gravity effects. We show the recent gravitational wave spectrum observed by several pulsar timing array projects can help constrain such effects.

8.Solar neutrinos and $ν_2$ visible decays to $ν_1$

Authors:André de Gouvêa, Jean Weill, Manibrata Sen

Abstract: Experimental bounds on the neutrino lifetime depend on the nature of the neutrinos and the details of the potentially new physics responsible for neutrino decay. In the case where the decays involve active neutrinos in the final state, the neutrino masses also qualitatively impact how these manifest themselves experimentally. In order to further understand the impact of nonzero neutrino masses, we explore how observations of solar neutrinos constrain a very simple toy model. We assume that neutrinos are Dirac fermions and there is a new massless scalar that couples to neutrinos such that a heavy neutrino - $\nu_2$ with mass $m_2$ - can decay into a lighter neutrino - $\nu_1$ with mass $m_1$ - and a massless scalar. We find that the constraints on the new physics coupling depend, sometimes significantly, on the ratio of the daughter-to-parent neutrino masses, and that, for large enough values of the new physics coupling, the "dark side" of the solar neutrino parameter space - $\sin^2\theta_{12}\sim 0.7$ - provides a reasonable fit to solar neutrino data. Our results generalize to other neutrino-decay scenarios, including those that mediate $\nu_2\to\nu_1\bar{\nu}_3\nu_3$ when the neutrino mass ordering is inverted mass and $m_2>m_1\gg m_3$, the mass of $\nu_3$.

9.CaloScore v2: Single-shot Calorimeter Shower Simulation with Diffusion Models

Authors:Vinicius Mikuni, Benjamin Nachman

Abstract: Diffusion generative models are promising alternatives for fast surrogate models, producing high-fidelity physics simulations. However, the generation time often requires an expensive denoising process with hundreds of function evaluations, restricting the current applicability of these models in a realistic setting. In this work, we report updates on the CaloScore architecture, detailing the changes in the diffusion process, which produces higher quality samples, and the use of progressive distillation, resulting in a diffusion model capable of generating new samples with a single function evaluation. We demonstrate these improvements using the Calorimeter Simulation Challenge 2022 dataset.

10.One-loop Effective Action up to Dimension Eight: Integrating out Heavy Fermion(s)

Authors:Joydeep Chakrabortty, Shakeel Ur Rahaman, Kaanapuli Ramkumar

Abstract: We present the universal one-loop effective action up to dimension eight after integrating out heavy fermion(s) using the Heat-Kernel method. We have discussed how the Dirac operator being a weak elliptic operator, the fermionic operator still can be written in the form of a strong elliptic one such that the Heat-Kernel coefficients can be used to compute the fermionic effective action. This action captures the footprint of both the CP conserving as well as violating UV interactions. As it does not rely on the specific forms of either UV or low energy theories, can be applicable for a very generic action. Our result encapsulates the effects of heavy fermion loops only.

11.A natural QCD infrared cutoff

Authors:A. A. Natale

Abstract: We briefly discuss some results obtained recently about dynamical gluon mass generation. We comment that this mass provides a natural QCD infrared cutoff and also implies an infrared finite coupling constant. We also discuss the phenomenological applications of these results and how they can be treated in the context of the so-called Dynamical Perturbation Theory.

1.Sommerfeld enhancement for puffy self-interacting dark matter

Authors:Wenyu Wang, Wu-Long Xu, Jin Min Yang, Bin Zhu, Rui Zhu

Abstract: We examine the Sommerfeld enhancement effect for the puffy self-interacting dark matter. We find out two new parameters to classify the self-scattering cross section into the Born, the resonance and the classical regimes for the puffy dark matter. Then we observe that the resonance peaks for the puffy dark matter self-scattering and for the Sommerfeld enhancement effect have the same locations. Further, we find that for a large ratio between $R_{\chi}$ (radius of a puffy dark matter particle) and $1/m_{\phi}$ (force range), the Sommerfeld enhancement factor approaches to 1 (no enhancement). Finally, for the puffy SIDM scenario to solve the small-scale problems, the values of the Sommerfeld enhancement factor are displayed in the allowed parameter regions.

2.An Improved Bound on Accelerated Light Dark Matter

Authors:Liangliang Su, Lei Wu, Bin Zhu

Abstract: Light (sub-GeV) dark matter is of growing interest in direct detection. Accelerated dark matter presents itself as a promising candidate capable of generating detectable nuclear recoil energy within the sub-GeV range. Due to the large kinetic energy, its interactions with the nucleus are predominantly governed by inelastic scattering, including quasi-elastic and deep inelastic scattering. In this work, we calculate the inelastic effects in the dark matter-Earth scattering mediated by a vector particle. Our analysis reveals that the impact of the inelastic scattering relies on the mediator mass and the kinetic energy spectrum of dark matter. The results exhibit a significant disparity, with the upper bounds of the exclusion limit for the spin-independent cross section between accelerated dark matter and nuclei via a heavy mediator differing by several tens of times when inelastic scattering is taken into account.

3.A possible search for Majorana neutrinos at future lepton colliders

Authors:E. Antonov, A. Drutskoy, M. Dubinin

Abstract: We discuss the process $\ell^+\ell^- \to N W^{\pm} \ell^{\mp}$, where $N$ is a heavy Majorana neutrino and $\ell = e, \mu$. Large cross sections are expected for these processes at high center-of-mass energies, which can be reached at future lepton-lepton colliders. The Monte Carlo simulation of the studied processes is produced within the framework of the seesaw type-I model, where the Majorana neutrinos (or heavy neutral leptons, HNL), are introduced in the standard leptonic sector. Recently the possibility to search for the direct HNL production was studied in the $\ell^+\ell^- \to N \nu_{\ell}$ process with the subsequent decay $N \to W^{\pm} \ell^{\mp}$. In this paper we investigate an alternative process $\ell^+\ell^- \to N W^{\pm} \ell^{\mp} \to W^{\pm}W^{\pm}\,\ell^{\mp}\,\ell^{\mp}$ with the lepton number violation by two units. The similar processes appear in collisions with the same-sign beams, $e^-e^- \to N W^-\,e^- \to W^-\,W^-\,e^+\,e^-$ or $\mu^+\mu^+ \to N W^+\,\mu^+ \to W^+\,W^+\,\mu^+\,\mu^-$. The cross sections of the processes under consideration are enhanced by the soft photon exchange in the $t$-channel. We calculate the cross sections for the signals and potential Standard Model backgrounds for the $e^+e^-$ beam collisions at the 1 TeV center-of-mass energy and the $\mu^+\mu^-$ collisions at 3 TeV and 10 TeV. Due to the diagrams with soft $t$-channel photons and respective interference the promptly emitted leptons are produced in the direction close to the corresponding beam. These leptons will be lost in the beam pipe or badly measured by forward detectors. However, the signal events can be well separated from backgrounds using the rest of the event containing the $WW\ell$ particles. Finally, the expected upper limits on the mixing parameters $|V_{\ell N}|^2$ as a function of M($N$) are calculated.

4.Estimates on the isospin-violating $Λ_b\rightarrow Σ^0 φ, Σ^0 J/ψ$ decays and the $Σ-Λ$ mixing

Authors:Zhou Rui, Jia-Ming Li, Chao-Qi Zhang

Abstract: We analyse the two purely isospin-violating decays $\Lambda_b\rightarrow \Sigma^0 \phi$ and $\Lambda_b\rightarrow \Sigma^0 J/\psi$, proceed merely via the exchange topologies, in the framework of perturbative QCD approach. Assuming $\Sigma^0$ baryon belongs to the idealized isospin triplet with quark components of $usd$, the branching ratios of the two decay modes are predicted to be tiny, of the order $10^{-8}-10^{-9}$, leading to a difficulty in observing them. We then extend our study to include the $\Sigma-\Lambda$ mixing.It is found that the mixing has significant effect on the $\Lambda_b\rightarrow \Sigma$ decays, especially it can greatly increase the rate of the $J/\psi$ process, by as much as two orders of magnitude, yield $10^{-7}$, which should be searchable in the future. We also estimate a set of asymmetry observables with and without the mixing effect, which will be tested in coming experiments.

5.The decay property of the $X(3842)$ as the $ψ_{_3}(1^3D_{_3})$ state

Authors:Wei Li, Su-Yan Pei, Tianhong Wang, Tai-Fu Feng, Guo-Li Wang

Abstract: In this paper, the new particle $X(3842)$ discovered by the LHCb Collaboration is identified to be the $\psi_{_3}(1^3D_{_3})$ state. We study its strong decays with the combination of the Bethe-Salpeter method and the $^3P_{_0}$ model. Its electromagnetic (EM) decay is also calculated by the Bethe-Salpeter method within Mandelstam formalism. The strong decay widths are {$\Gamma[X(3842)\rightarrow D^{0}\bar{D}^{0}]=1.28$ MeV}, $\Gamma[X(3823)\rightarrow D^{+}D^{-}]=1.08$ MeV, and the ratio ${\cal B}[X(3842)\rightarrow D^{+}D^{-}]/{\cal B}[X(3823)\rightarrow D^{0}\bar{D}^{0}]=0.84$. The EM decay width is $\Gamma[X(3842)\rightarrow\chi_{_{c2}}\gamma]=0.29$ MeV. We also estimate the total width to be 2.87 MeV, which is in good agreement with the experimental data $2.79^{+0.86}_{-0.86}$ MeV. Since the used relativistic wave functions include different partial waves, we also study the contributions of different partial waves in electromagnetic decay.

6.Regge trajectories for the heavy-light diquarks

Authors:Jiao-Kai Chen, Xia Feng, Jia-Qi Xie

Abstract: We attempt to apply the Regge trajectory approach to the heavy-light diquarks composed of one heavy quark and one light quark. However, we find that the direct application of the usual Regge trajectory formula for the heavy-light mesons and baryons fails. In order to correctly estimate the masses of the heavy-light diquarks, it is needed to consider the light quark mass correction and the parameter $C$ in the Cornell potential $-\alpha/r+{\sigma}r+C$ within the Regge trajectory formula. By using the modified Regge trajectory formulas, we are able to estimate the masses of the heavy-light diquarks $(cu)$, $(cs)$, $(bu)$ and $(bs)$, which agree with other theoretical results. It is illustrated that the heavy-light diquarks satisfy the universal descriptions irrespective of heavy quark flavors, similar to other heavy-light systems such as the heavy-light mesons, the heavy-light baryons composed of one heavy quark (diquark) and one light diquark (quark), and the heavy-light tetraquarks composed of one heavy diquark (antidiquark) and one light antidiquark (diquark). The diquark Regge trajectory provides a new and very simple approach for estimating the spectra of the heavy-light diquarks.

7.New physics implications of VBF searches exemplified through the Georgi-Machacek model

Authors:Manimala Chakraborti, Dipankar Das, Nivedita Ghosh, Samadrita Mukherjee, Ipsita Saha

Abstract: LHC searches for nonstandard scalars in vector boson fusion (VBF) production processes can be particularly efficient in probing scalars belonging to triplet or higher multiplet representations of the Standard Model $SU(2)_L$ gauge group. They can be especially relevant for models where the additional scalars do not have any tree-level couplings to the Standard Model fermions, rendering VBF as their primary production mode at the LHC. In this work, we employ the latest LHC data from VBF resonance searches to constrain the properties of nonstandard scalars, taking the Georgi-Machacek model as a prototypical example. We take into account the theoretical constraints on the potential from unitarity and boundedness-from-below as well as indirect constraints coming from the signal strength measurements of the 125 GeV Higgs boson at the LHC. To facilitate the phenomenological analysis we advocate a convenient reparametrization of the trilinear couplings in the scalar potential. We derive simple correlations among the model parameters corresponding to the decoupling limit of the model. We explicitly demonstrate how a combination of theoretical and phenomenological constraints can push the GM model towards the decoupling limit. Our analysis suggests that the VBF searches can provide key insights into the composition of the electroweak vacuum expectation value.

8.Effects of odderon spin on helicity amplitudes in $pp$ elastic scattering

Authors:Prin Sawasdipol, Jingle B. Magallanes, Chakrit Pongkitivanichkul, Daris Samart

Abstract: In recent years, the discovery of the odderon, a colorless $C$-odd gluonic compound, has been confirmed in the TOTEM and D0 collaborations. However, the spin quantum number of the odderon remains unidentified. In this work, we aim to attribute a spin of $J=3$ to the odderon in $pp$ elastic scattering by calculating the helicity amplitudes and the corresponding complex parameter $r_5$, the ratio of helicity's single-flip to non-flip amplitudes, for the spin-3 tensor odderon with the standard spin-2 tensor pomeron exchanges. Then, we apply these results to the constraints obtained from the STAR experiment at RHIC. By comparing to the contributions of the spin-1 vector odderon and spin-2 tensor pomeron, we demonstrate that the spin-3 tensor odderon, i.e. $J=3$, provides a better explanation for the observable in $pp$ elastic scattering.

9.Forward production of a Drell-Yan pair and a jet at small $x$ at next-to-leading order

Authors:Pieter Taels

Abstract: We perform the analytical next-to-leading order calculation of the process $p+A\to \gamma^{*}+\mathrm{jet}+X$, at forward rapidities and low $x$. These kinematics justify a hybrid approach, where a quark from the \textquoteleft projectile' proton scatters off the gluon distribution of the \textquoteleft target', which can be a nucleus or a highly boosted proton. By using the Color Glass Condensate effective theory approach, this gluon distribution is allowed to be so dense that the quark undergoes multiple scattering. Moreover, large high-energy logarithms in the ratio of the hard scale and the center-of-mass energy are resummed by the Balitsky, Kovchegov, Jalilian-Marian, Iancu, McLerran, Weigert, Leonidov, Kovner or BK-JIMWLK evolution equations. We demonstrate that all ultraviolet divergences encountered in the calculation cancel, while the high-energy divergences are absorbed into BK-JIMWLK. The remaining singularities are collinear in nature and can be either absorbed into the Dokshitzer-Gribov-Lipatov-Altarelli-Parisi evolution of the incoming quark, when they stem from initial-state radiation, or else can be treated by introduction of a jet function in case they are caused by final-state emissions. The resulting cross section is completely finite and expressed in function of only a small set of color operators.

1.Light-by-light scattering in ultraperipheral collisions of heavy ions with future FoCal and ALICE 3 detectors

Authors:P. Jucha, M. Klusek-Gawenda, A. Szczurek

Abstract: We discuss possible future studies of photon-photon (light-by-light) scattering using a planned FoCal and ALICE 3 detectors. We include different mechanisms of $\gamma\gamma\to\gamma\gamma$ scattering, such as double-hadronic photon fluctuations, $t/u$-channel neutral pion exchange or resonance excitations ($\gamma \gamma \to R$) and deexcitation ($R \to \gamma \gamma$). The broad range of (pseudo)rapidities and lower cuts on transverse momenta open a necessity to consider not only dominant box contributions but also other subleading contributions. Here we include low mass resonant $R = \pi^0$, $\eta$, $\eta'$ contributions. The resonance contributions give intermediate photon transverse momenta. However, these contributions can be eliminated by imposing windows on di-photon invariant mass. We study and quantify individual box contributions (leptonic, quarkish). The electron/positron boxes dominate at low $M_{\gamma \gamma}<1$ GeV di-photon invariant masses. The PbPb$\to$PbPb$\gamma \gamma$ cross section is calculated within equivalent photon approximation in the impact parameter space. Several differential distributions are presented and discussed. We consider four different kinematic regions. We predict cross section in the (mb-b) range for typical ALICE 3 cuts, a few orders of magnitude larger than for the current ATLAS or CMS experiments. We also consider the two-$\pi^0$ background which can, in principle, be eliminated at the new kinematical range for the ALICE 3 measurements by imposing dedicated cuts on di-photon transverse momentum and\or so-called vector asymmetry.

2.New Constraint on Dark Photon at T2K Off-Axis Near Detector

Authors:Takeshi Araki, Kento Asai, Tomoya Iizawa, Hidetoshi Otono, Takashi Shimomura, Yosuke Takubo

Abstract: The T2K experiment is one of the most powerful long-baseline experiments to investigate neutrino oscillations. The off-axis near detector called ND280 is installed 280 m downstream from the neutrino production target to measure the neutrino energy spectrum. In this paper, we study the capability of the ND280 detector to search for the dark photon produced through the meson rare decay and proton bremsstrahlung processes at the proton beam dump. We find that the ten-year operation of T2K with the ND280 detector excludes the unexplored parameter region for the dark photon mass and kinetic mixing. We also show that a broader parameter region can be searched by the ND280 in the future T2K operation for dark photon as well as U(1)$_{B-L}$ gauge boson.

3.Spectral properties of $ω$, $ρ$ and $A_1$ mesons in hot magnetized matter: effects of (inverse) magnetic catalysis

Authors:Pallabi Parui, Amruta Mishra

Abstract: In-medium masses of the light vector $\omega$, $\rho$ and axial-vector $A_1$ mesons are studied in the magnetized nuclear matter, accounting for the effects of (inverse) magnetic catalysis at finite temperature. The in-medium partial decay widths for the $A_1\rightarrow \rho \pi$ channels are studied from the in-medium masses of the initial and the final state particles, by applying a phenomenological Lagrangian to account for the $A_1\rho\pi$ interaction vertices. The masses are calculated within the QCD sum rule framework, with the medium effects coming through the light quark ($\sim \langle \bar{q}q \rangle$) and the scalar gluon condensates ($\sim \langle G^2 \rangle$), as well as the light four-quark condensate ($\sim \langle \bar{q}q\rangle^2 $). The condensates are calculated within the chiral $SU(3)$ model in terms of the medium modified scalar fields: isoscalar $\sigma$, $\zeta$, isovector $\delta$ and the dilaton field $\chi$. The effects of magnetic fields are incorporated through the magnetized Dirac sea contribution as well as the Landau energy levels of protons and anomalous magnetic moments (AMMs) of the nucleons at finite temperature nuclear matter. The incorporation of the magnetic field through the Dirac sea of nucleons lead to an enhancement (reduction) of the light quark condensates with magnetic field, give rise to the phenomenon of magnetic (inverse) catalysis. The effects of (inverse) magnetic catalysis at finite temperature nuclear matter are studied on the spectral functions and production cross-sections of the neutral $\rho$ and $A_1$ mesons. This may affect the production of the light vector and axial-vector mesons in the peripheral heavy-ion collision experiments, where estimated magnetic field is very large at the early stages of collisions with very high temperature.

4.Momentum spectrum of Schwinger pair production in four-dimensional e-dipole fields

Authors:Gianluca Degli Esposti, Greger Torgrimsson

Abstract: We calculate the momentum spectrum of electron-positron pairs created via the Schwinger mechanism by a class of four-dimensional electromagnetic fields called e-dipole fields. To the best of our knowledge, this is the first time the momentum spectrum has been calculated for 4D, exact solutions to Maxwell's equations. Moreover, these solutions give fields that are optimally focused, and are hence particularly relevant for future experiments. To achieve this we have developed a worldline instanton formalism where we separate the process into a formation and an acceleration region.

5.Conversion of protons to positrons by a black hole

Authors:A. D. Dolgov, A. S. Rudenko

Abstract: The conversion of protons to positrons at the horizon of a black hole (BH) is considered. It is shown that the process may efficiently proceed for BHs with masses in the range $\sim 10^{18}$ -- $10^{21}$ g. It is argued that the electric charge of BH acquired by the proton accretion to BH could create electric field near BH horizon close to the critical Schwinger one. It leads to efficient electron-positron pair production, when electron is back capture by the BH while positron is emitted into outer space. The electron-positron annihilation in the interstellar medium may explain the origin of the observed 511 keV line.

6.Multi-photon signatures as a probe of CP-violation in extended Higgs sectors

Authors:Shinya Kanemura, Kento Katayama, Tanmoy Mondal, Kei Yagyu

Abstract: We propose a novel signature with four-photon final states to probe CP-violating (CPV) extended Higgs sectors via $f \bar{f} \to Z^* \to H_1H_2 \to 4 \gamma$ processes with $H_{1,2}$ being additional neutral Higgs bosons. We focus on the nearly Higgs alignment scenario, in which the discovered Higgs boson almost corresponds to a neutral scalar state belonging to the isospin doublet field with the vacuum expectation value $v \simeq 246$ GeV. We show that the branching ratios of $H_{1,2} \to \gamma \gamma$ can simultaneously be sizable when CPV phases in the Higgs potential are of order one due to the enhancement of charged-Higgs boson loops. Such branching ratios can be especially significant when the fermiophobic scenario is taken into account. As a simple example, we consider the general two Higgs doublet model, and demonstrate that the cross section for the four-photon process can be 0.1 fb at LHC with the masses of $H_{1,2}$ to be a few 100 GeV in the Higgs alignment limit under the constraints from electric dipole moments (EDMs) and LHC Run-II data. We also illustrate that the searches for EDMs and di-photon resonances at high-luminosity LHC play complementary roles to explore CPV extended Higgs sectors.

1.Excitation spectra of heavy baryons in a quark-diquark model with relativistic corrections

Authors:S. Kinutani, H. Nagahiro, D. Jido

Abstract: The excitation spectra of \Lambda_c and \Lambda_b baryons are investigated by using a quark-diquark model in which a single-heavy baryon is treated as the bound state of a heavy quark and a scalar diquark. We take two types of relativistic corrections into account for the quark-diquark potential. In the first type, we consider the one-gluon exchange between the heavy quark and one of the light quarks in the diquark. In the second, we consider the one-gluon exchange between a scalar particle and a heavy quark. We find that there is a large difference between two types of corrections due to different treatment of the internal color structure of the diquark. The relativistic corrections are important for the solution to the string tension puzzle, particularly, the Darwin term makes a large contribution.

2.Molecular pentaquark states with open charm and bottom flavors

Authors:Jia-Xin Lin, Hua-Xing Chen, Wei-Hong Liang, Wen-Ying Liu, Dan Zhou

Abstract: We study the possibly-existing molecular pentaquark states with open charm and bottom flavors, {\it i.e.}, the states with the quark contents $c\bar{b}qqq$ and $b\bar{c}qqq$ ($q=u,d,s$). We investigate the meson-baryon interactions through the coupled-channel unitary approach within the local hidden-gauge formalism, and extract the poles by solving the Bethe-Salpeter equation in coupled channels. These poles qualify as molecular pentaquark states, which are dynamically generated from the meson-baryon interactions through the exchange of vector mesons. We calculate their masses and widths as well as their couplings to various coupled channels. Our results suggest the existence of the $\Sigma_c^{(*)} B^{(*)}$ and $\Sigma_b^{(*)} \bar{D}^{(*)}$ molecular states with isospin $I=1/2$ as well as the $\Xi_c^{(\prime,*)} B^{(*)}$ and $\Xi_b^{(\prime,*)} \bar{D}^{(*)}$ molecular states with isospin $I=0$.

3.Exploring CP Violation beyond the Standard Model and the PQ Quality with Electric Dipole Moments

Authors:Kiwoon Choi, Sang Hui Im, Krzysztof Jodłowski

Abstract: In some models of physics beyond the Standard Model (SM), one of the leading low energy consequences of the model appears in the form of the chromoelectric dipole moments (CEDMs) of the gluons and light quarks. We examine if these CEDMs can be distinguished from the QCD $\theta$-term through the experimentally measurable nucleon and atomic electric dipole moments (EDMs) in both cases with and without the Peccei-Quinn (PQ) mechanism solving the strong CP problem. We find that the nucleon EDMs can show a distinctive pattern when the EDMs are dominantly induced by light quark CEDMs without the PQ mechanism. In the presence of the PQ mechanism, the nucleon EDMs due to the gluon or light quark CEDMs have a similar pattern as those due to the QCD $\theta$-parameter, regardless of the origin of the axion vacuum value which determines the $\theta$-parameter. In contrast, diamagnetic atomic EDMs due to the gluon or light quark CEDMs have characteristic patterns distinguishable from the pattern due to the $\theta$-parameter which is induced dominantly by UV-originated PQ breaking other than the QCD anomaly, for instance by quantum gravity effects. Our results suggest that EDMs may provide information not only on CP violation beyond the SM, but also on the existence of the PQ mechanism and the quality of the PQ symmetry characterized by the strength of UV-originated PQ breaking other than the QCD anomaly.

4.Weak interaction corrections to muon pair production via the photon fusion at the LHC

Authors:S. I. Godunov, E. K. Karkaryan, V. A. Novikov, A. N. Rozanov, M. I. Vysotsky, E. V. Zhemchugov

Abstract: Analytical formulas describing the correction due to the $Z$ boson exchange to the cross section of the reaction $pp\rightarrow p\mu^+\mu^- X$ are presented. When the invariant mass of the produced muon pair $W\gtrsim 150~\text{GeV}$ and its total transverse momentum is large, the correction is of the order of 20%.

5.Picturing QCD jets in anisotropic matter: from jet shapes to Energy Energy Correlators

Authors:João Barata, José Guilherme Milhano, Andrey V. Sadofyev

Abstract: Recent theoretical developments in the description of jet evolution in the quark gluon plasma have allowed to account for the effects of hydrodynamic gradients in the medium modified jet spectra. These constitute a crucial step towards using jets as tomographic probes of the nuclear matter they traverse. In this work, we complement these studies by providing leading order calculations of widely studied jet observables, taking into account matter anisotropies. We show that the energy distribution inside a jet is pushed towards the direction of the largest matter anisotropy, while the away region is depleted. As a consequence, the jet mass and girth gain a non-trivial azimuthal dependence, with the average value of the distribution increasing along the direction of largest gradients. However, we find that, for these jet shapes, matter anisotropic effects can be potentially suppressed by vacuum Sudakov factors. We argue that the recently proposed measurements of energy correlations within jets do not suffer from such effects, with the azimuthal dependence being visible in a large angular window, regardless of the shape of the distribution.

1.Absorption of Fermionic Dark Matter via the Scalar Portal

Authors:Peter Cox, Matthew J. Dolan, Joshua Wood

Abstract: The absorption of fermionic dark matter has recently been studied as a signature for the direct detection of dark matter. We construct the first UV completion of the scalar effective operator associated with this signature. We calculate the constraints on the model and demonstrate there is viable parameter space which can be probed by a next-generation experiment such as XLZD. We also consider the cosmological history of our model and show that the correct relic abundance can be obtained via freeze-out in the dark sector. However, within this minimal model, we find that the absorption signal is highly suppressed in the parameter space that yields the correct relic abundance.

2.Inclusive, prompt and non-prompt $\rm{J}/ψ$ identification in proton-proton collisions at the Large Hadron Collider using machine learning

Authors:Suraj Prasad, Neelkamal Mallick, Raghunath Sahoo

Abstract: Studies related to $\rm{J}/\psi$ meson, a bound state of charm and anti-charm quarks ($c\bar{c}$), in heavy-ion collisions, provide genuine testing grounds for the theory of strong interaction, quantum chromodynamics (QCD). To better understand the underlying production mechanism, cold nuclear matter effects, and influence from the quark-gluon plasma, baseline measurements are also performed in proton-proton ($pp$) and proton-nucleus ($p$--A) collisions. The inclusive $\rm{J}/\psi$ measurement has contributions from both prompt and non-prompt productions. The prompt $\rm{J}/\psi$ is produced directly from the hadronic interactions or via feed-down from directly produced higher charmonium states, whereas non-prompt $\rm{J}/\psi$ comes from the decay of beauty hadrons. In experiments, $\rm{J}/\psi$ is reconstructed through its electromagnetic decays to lepton pairs, in either $e^{+}+e^{-}$ or $\mu^{+}+\mu^{-}$ decay channels. In this work, for the first time, machine learning techniques are implemented to separate the prompt and non-prompt dimuon pairs from the background to obtain a better identification of the $\rm{J}/\psi$ signal for different production modes. The study has been performed in $pp$ collisions at $\sqrt{s} = 7$ and 13 TeV simulated using PYTHIA8. Machine learning models such as XGBoost and LightGBM are explored. The models could achieve up to 99\% prediction accuracy. The transverse momentum ($p_{\rm T}$) and rapidity ($y$) differential measurements of inclusive, prompt, and non-prompt $\rm{J}/\psi$, its multiplicity dependence, and the $p_{\rm T}$ dependence of fraction of non-prompt $\rm{J}/\psi$ ($f_{\rm B}$) are shown. These results are compared to experimental findings wherever possible.

3.Gravitational waves effects and phenomenology of a two-component dark matter model

Authors:Mojtaba Hosseini, Seyed Yaser Ayazi, Ahmad Mohamadnejad

Abstract: We study an extension of the Standard Model (SM) with two candidates for dark matter (DM) which includes a Dirac fermion and a Vector Dark Matter (VDM) under new $U(1)$ gauge group in the hidden sector. The model is classically scale invariant and the electroweak symmetry breaks because of the loop effects. We investigate the model parameter space allowed by current experimental constraints and phenomenological bounds. It is shown that the model can be satisfied for the large part of parameter space of VDM mass and fermion dark matter mass, i.e., $400< M_V<3000$ GeV and $M_{\psi}<400$ GeV.The electroweak phase transition have been discussed and shown that there is region in the parameter space of the model consistent with DM relic density, direct detection and collider constraints, while at the same time can lead to first order electroweak phase transition. The gravitational waves produced during the phase transition could be probed by future space-based interferometers such as LISA and BBO.

4.Probing proton structure with $c \bar c$ correlations in ultraperipheral $pA$ collisions

Authors:Barbara Linek, Agnieszka Łuszczak, Marta Łuszczak, Roman Pasechnik, Wolfgang Schäfer, Antoni Szczurek

Abstract: We study the exclusive diffractive $c \bar c$ photoproduction in ultraperipheral $pA$ collisions. The formalism makes use of off-diagonal generalizations of the unintegrated gluon distribution, the so-called generalized transverse momentum dependent distributions (GTMDs). We present two different formulations. The first one is based directly on gluon GTMD parametrizations in momentum space. Another option is the calculation of the GTMD as a Fourier transform of the dipole-nucleon scattering amplitude $N(Y,\vec{r}_{\perp},\vec{b}_{\perp})$. The latter approach requires some extra regularization discussed in the paper. Different dipole amplitudes from the literature are used. Compared to previous calculations in the literature, we integrate over the full phase space and therefore cross sections for realistic conditions are obtained. We present distributions in rapidity of $c$ or $\bar c$, transverse momentum of the $c \bar c$ pair, four-momentum transfer squared as well as the azimuthal correlation between a sum and a difference of the $c$ and $\bar c$ transverse momenta. The azimuthal correlations are partially due to the so-called elliptic gluon Wigner distribution. Different models lead to different modulations in the azimuthal angle. The modulations are generally smaller than 5%. They depend on the range of transverse momentum selected for the calculation.

5.Updated Trends in Neutrino-induced hadron production

Authors:Rashi Sharma, R. Aggarwal, M. Kaur

Abstract: With four different type of neutrino-induced interactions, we considered to investigate and reanalyse the KNO scaling in modified multiplicity distributions from a different perspective. In an attempt of first of its kind, we propose alternate fitting function to parameterise the distribution than the most widely adopted Slattery's function and compare it with yet another form. We propose the shifted Gompertz and Weibull functions as the fitting functions and compare their potency for the most conventional form of Slattery's function. In addition the analysis of the data by evaluating the central moments and factorial moments, we show the dependence of moments on the target size.

6.Shrinking the Warm Little Inflaton

Authors:Paulo B. Ferraz, João G. Rosa

Abstract: We show that warm inflation can be successfully realized in the high temperature regime through dissipative interactions between the inflaton and a single fermionic degree of freedom, provided that the latter's mass is an oscillatory function of the inflaton field value. We demonstrate, in particular, that despite the consequent large amplitude oscillations of the eta slow-roll parameter, their effect is, on average, sufficiently suppressed to allow for a slow-roll trajectory. In addition, we demonstrate that, even though this also induces a parametric resonance that amplifies inflaton perturbations, this has a negligible effect on CMB scales in the relevant parametric range. Hence, the "Warm Little Inflaton" scenario can be realized with one less fermionic degree of freedom and no need of imposing an additional discrete interchange symmetry.

7.Study on the possible molecular states composed of $Λ_c\bar D^*$, $Σ\bar D^*$, $Ξ_c\bar D^*$ and $Ξ_c'\bar D^*$ in the Bethe-Salpeter frame based on the pentaquark states $P_c(4440)$, $P_c(4457)$ and $P_{cs}(4459)$

Authors:Hong-Wei Ke, Fang Lu, Hai Pang, Xiao-Hai Liu, Xue-Qian Li

Abstract: The measurements on a few pentaquarks states $P_c(4440)$, $P_c(4457)$ and $P_{cs}(4459)$ excite our new interests about their structures. Since the masses of $P_c(4440)$ and $P_c(4457)$ are close to the threshold of $\Sigma_c\bar D^*$, in the earlier works, they were regarded as molecular states of $\Sigma_c\bar D^*$ with quantum numbers $I(J^P)=\frac{1}{2}(\frac{1}{2}^-)$ and $\frac{1}{2}(\frac{3}{2}^-)$, respectively. In a similar way $P_{cs}(4459)$ is naturally considered as a $\Xi_c\bar D^*$ bound state with $I=0$. Within the Bethe-Salpeter (B-S) framework we systematically study the possible bound states of $\Lambda_c\bar D^*$, $\Sigma\bar D^*$, $\Xi_c\bar D^*$ and $\Xi_c'\bar D^*$. Our results indicate that $\Sigma_c\bar D^*$ can form a bound state with $I(J^P)=\frac{1}{2}(\frac{1}{2}^-)$, which corresponds to $P_c(4440)$. However for the $I(J^P)=\frac{1}{2}(\frac{3}{2}^-)$ system the attraction between $\Sigma$ and $\bar D^*$ is too weak to constitute a molecule, so $P_{c}(4457)$ may not be a bound state of $\Sigma\bar D^*$ with $I(J^P)=\frac{1}{2}(\frac{3}{2}^-)$. As $\Xi_c\bar D^*$ and $\Xi_c'\bar D^*$ systems we take into account of the mixing between $\Xi_c$ and $\Xi'_c$ and the eigenstets should include two normal bound states $\Xi_c\bar D^*$ and $\Xi_c'\bar D^*$ with $I(J^P)=\frac{1}{2}(\frac{1}{2}^-)$ and a loosely bound state $\Xi_c\bar D^*$ with $I(J^P)=\frac{1}{2}(\frac{3}{2}^-)$. The conclusion that two $\Xi_c\bar D^*$ bound states exist, supports the suggestion that the observed peak of $P_{cs}(4459)$ may hide two states $P_{cs}(4455)$ and $P_{cs}(4468)$. Based on the computations we predict a bound state $\Xi_c'\bar D^*$ with $I(J^P)=\frac{1}{2}(\frac{1}{2}^-)$ but not that with $I(J^P)=\frac{1}{2}(\frac{3}{2}^-)$. Further more accurate experiments will test our approach and results.

8.Exploring robust correlations between fermionic dark matter model parameters and neutron star properties: A two-fluid perspective

Authors:Prashant Thakur, Tuhin Malik, Arpan Das, T. K. Jha, Constança Providência

Abstract: The current observational properties of neutron stars have not definitively ruled out the possibility of dark matter. In this study, we primarily focus on exploring correlations between the dark matter model parameters and different neutron star properties using a rich set of EOSs. We adopt a two-fluid approach to calculate the properties of neutron stars. For the nuclear matter EOS, we employ several realistic EOS derived from the relativistic mean field model (RMF), each exhibiting varying stiffness and composition. In parallel, we look into the dark matter EOS, considering fermionic matter with repulsive interaction described by a relativistic mean field Lagrangian. A reasonable range of parameters is sampled meticulously. Interestingly, our results reveal a promising correlation between the dark matter model parameters and stellar properties, particularly when we ignore the uncertainties in the nuclear matter EOS. However, when introducing uncertainties in the nuclear sector, the correlation weakens, suggesting that the task of conclusively constraining any particular dark matter model might be challenging using global properties alone, such as mass, radius, and tidal deformability. Notably, we find that dark-matter admixed stars tend to have higher central baryonic density, potentially allowing for non-nucleonic degrees of freedom or direct Urca processes in stars with lower masses. There is also a tantalizing hint regarding the detection of stars with the same mass but different surface temperatures, which may indicate the presence of dark matter. With our robust and extensive dataset, we delve deeper and demonstrate that even in the presence of dark matter, the semi-universal C-Love relation remains intact.

1.Investigation on the higher twist TMD $h_3$ for proton in the light-front quark-diquark model

Authors:Shubham Sharma, Harleen Dahiya

Abstract: The higher twist T-even transverse momentum dependent distribution (TMD) $h_3(x, {\bf p_\perp^2})$ for the proton has been examined in the light-front quark-diquark model (LFQDM). By deciphering the unintegrated quark-quark correlator for semi-inclusive deep inelastic scattering (SIDIS), we have derived explicit equations of the TMD for both the scenarios when the diquark is a scalar or a vector. Average as well as average square transverse momenta have been computed for this TMD. Additionally, we have discussed its transverse momentum dependent parton distribution function (TMDPDF) $h_3(x)$.

2.Predictions of $m_{ee}$ and neutrino mass from a consistent Froggatt-Nielsen model

Authors:Yu-Cheng Qiu, Jin-Wei Wang, Tsutomu T. Yanagida

Abstract: The seesaw mechanism is the most attractive mechanism to explain the small neutrino masses, which predicts the neutrinoless double beta decay ($0\nu\beta\beta$) of the nucleus. Thus the discovery of $0\nu\beta\beta$ is extremely important for future particle physics. However, the present data on the neutrino oscillation is not sufficient to predict the value of $m_{ee}$ as well as the neutrino mass $m_\nu^i$. In this short article, by adopting a simple and consistent Froggatt-Nielsen model, which can well explain the observed masses and mixing angles of quark and lepton sectors, we calculate the distribution of $m_{ee}$ and $m_\nu^i$. Interestingly, a relatively large part of the preferred parameter space can be detected in the near future.

3.R-parity Conserving Minimal SUSY U(1)$_{X}$ Model

Authors:Satsuki Oda, Nobuchika Okada, Nathan Papapietro, Dai-suke Takahashi

Abstract: We propose a minimal gauged U(1)$_X$ extension of the MSSM with R-parity conservation. In this model, U(1)$_X$ is a generalization of the well-known U(1) $B-L$. Apart from the MSSM particle content, the model includes three right-handed neutrino (RHN) chiral superfields, each carrying a unit U(1)$_X$ charge. In the presence of RHNs, the model is free from all gauge and mixed gauge-gravitational anomalies. However, there are no U(1)$_X$ Higgs chiral superfields with U(1)$_X$ charge $\pm2$ involved in the model. Two of the RHN superfields are assigned an odd R-parity, while the last one ($\Psi$) has an even parity. The U(1)$_X$ symmetry is radiatively broken by the VEV of the scalar component of $\Psi$. As a consequence of the absence of U(1)$_X$ Higgs fields and the novel R-parity assignment, the three light neutrinos consist of one massless neutrino and two Dirac neutrinos. In the early universe, the right-handed components of the Dirac neutrinos are in thermal equilibrium with the SM particles through the U(1)$_X$ gauge ($Z^\prime$) boson. The extra energy density from the RHNs is constrained to avoid disrupting the success of BBN, leading to a lower bound on the scale of U(1)$_X$ symmetry breaking. In our model, a mixture of the U(1)$_X$ gaugino and the fermionic component of $\Psi$ becomes a new dark matter (DM) candidate if it is the lightest sparticle mass eigenstate. We examine this DM phenomenology and identify a parameter region that reproduces the observed DM relic density. Furthermore, we consider constraints from the search for $Z'$ boson resonance at the LHC. The three constraints obtained from the success of BBN, the observed DM relic density, and the $Z^\prime$ resonance search at the LHC complement each other, narrowing down the allowed parameter region.

4.Rapidity gap distribution of diffractive small-$x_{I\hspace{-0.3em}P}$ events at HERA and at the EIC

Authors:Tuomas Lappi Department of Physics, University of Jyväskylä Helsinki Institute of Physics, Anh Dung Le Department of Physics, University of Jyväskylä Helsinki Institute of Physics, Heikki Mäntysaari Department of Physics, University of Jyväskylä Helsinki Institute of Physics

Abstract: We use the Kovchegov-Levin equation to resum contributions of large invariant mass diffractive final states to diffractive structure functions in the dipole picture of deep inelastic scattering. For protons we use a (modified) McLerran-Venugopalan model as the initial condition for the evolution, with free parameters obtained from fits to the HERA inclusive data. We obtain an adequate agreement to the HERA diffractive data in the moderately high-mass regimes when the proton density profile is fitted to the diffractive structure function data in the low-mass region. The HERA data is found to prefer a proton shape that is steeper than a Gaussian. The initial conditions are generalized to the nuclear case using the optical Glauber model. Strong nuclear modification effects are predicted in diffractive scattering off a nuclear target in kinematics accessible at the future Electron-Ion collider. In particular, the Kovchegov-Levin evolution has a strong effect on the Q 2 -dependence of the diffractive cross section.

5.Explainable Equivariant Neural Networks for Particle Physics: PELICAN

Authors:Alexander Bogatskiy, Timothy Hoffman, David W. Miller, Jan T. Offermann, Xiaoyang Liu

Abstract: We present a comprehensive study of the PELICAN machine learning algorithm architecture in the context of both tagging (classification) and reconstructing (regression) Lorentz-boosted top quarks, including the difficult task of specifically identifying and measuring the $W$-boson inside the dense environment of the boosted hadronic final state. PELICAN is a novel permutation equivariant and Lorentz invariant or covariant aggregator network designed to overcome common limitations found in architectures applied to particle physics problems. Compared to many approaches that use non-specialized architectures that neglect underlying physics principles and require very large numbers of parameters, PELICAN employs a fundamentally symmetry group-based architecture that demonstrates benefits in terms of reduced complexity, increased interpretability, and raw performance. When tested on the standard task of Lorentz-boosted top quark tagging, PELICAN outperforms existing competitors with much lower model complexity and high sample efficiency. On the less common and more complex task of four-momentum regression, PELICAN also outperforms hand-crafted algorithms. We discuss the implications of symmetry-restricted architectures for the wider field of machine learning for physics.

6.Measurement of the CPV Higgs mixing angle in ZZ-fusion at 1 TeV ILC

Authors:N. Vukašinović, I. Božović-Jelisavčić, G. Kačarević

Abstract: Although the studies of tensor structure of the Higgs boson interactions with vector bosons and fermions at CMS and ATLAS experiments have established that the $J^{\mathrm{PC}}$ quantum numbers of the Higgs boson should be $0^{++}$, small CP violation in the Higgs sector (up to 10% contribution of the CP-odd state) cannot be excluded with the current experimental precision. We review possibilities to measure CP violating mixing angle $\Psi_{\mathrm{CP}}$ between scalar and pseudoscalar states, at a linear electron-positron collider, at center-of-mass energy of 1 TeV.

7.Higgs self-coupling measurement at the International Linear Collider

Authors:Julie Munch Torndal, Jenny List

Abstract: The Higgs sector of particle physics is still largely uncovered, where establishing the Higgs mechanism is central to advance the field. The Higgs self-coupling is the key ingredient missing and an important puzzle piece for potentially uncovering new physics beyond the standard model. With the energy reach and precision reach of linear $e^+e^-$ colliders, the Higgs self-coupling can be measured directly and precisely enough that certain BSM scenarios can be evaluated. A new analysis of the capability to measure the Higgs self-coupling at the International Linear Collider (ILC) is ongoing and have identified aspects concerning the reconstruction tools which are expected to improve precision reach and are presented. This ongoing analysis intends to update the state-of-the-art projections for measuring the Higgs self-coupling at ILC which was previously evaluated at a centre-of-mass energy of 500 GeV. Additionally, the ongoing analysis intends to evaluate the choice of centre-of-mass energy and how it influences the reachable precision, as well as to consider how BSM effects might influence the reachable precision.

8.Quantum local-equilibrium state with fixed multiplicity constraint and Bose-Einstein momentum correlations

Authors:M. D. Adzhymambetov, S. V. Akkelin, Yu. M. Sinyukov

Abstract: The one- and two-boson momentum spectra are derived in the quantum local-equilibrium canonical ensemble of noninteracting bosons with a fixed particle number constraint. We define the canonical ensemble as a subensemble of events associated with the grand-canonical ensemble. Applying simple hydro-inspired parameterization with parameter values that correspond roughly to the values at the system's breakup in $p+p$ collisions at the LHC energies, we compare our findings with the treatment which is based on the grand-canonical ensembles where mean particle numbers coincide with fixed particle numbers in the canonical ensembles. We observe a significantly greater sensitivity of the two-particle momentum correlation functions to fixed multiplicity constraint compared to one-particle momentum spectra. The results of our analysis may be useful for interpretation of multiplicity-dependent measurements of $p+p$ collision events.

9.Equilibration of quantum many-body fast neutrino flavor oscillations

Authors:Joshua D. Martin, Duff Neill, A. Roggero, Huaiyu Duan, J. Carlson

Abstract: In hot and dense astrophysical environments, neutrinos are emitted in such numbers that their flavor content is expected to have an appreciable effect on the local system's dynamic and chemical evolution. In this work, we consider such a gas in the regime for which neutrino-neutrino coherent forward scattering dominates the flavor evolution. We show evidence that the generic potential induced by this effect is non-integrable and that the statistics of its energy level spaces are in good agreement with the Wigner surmise. We also find that individual neutrinos rapidly entangle with all of the others present which results in an equilibration of the flavor content of individual neutrinos. We show that the average neutrino flavor content can be predicted utilizing a thermodynamic partition function. A random phase approximation to the evolution gives a simple picture of this equilibration. In the case of neutrinos and antineutrinos, processes like $\nu_e {\bar{\nu}}_e \leftrightarrows \nu_\mu {\bar{\nu}_\mu} $ yield a rapid equilibrium satisfying $n( \nu_e) n({\bar \nu}_e) = n( \nu_\mu) n({\bar \nu}_\mu) = n( \nu_\tau) n({\bar \nu}_\tau)$ in addition to the standard lepton number conservation in regimes where off-diagonal vacuum oscillations are small compared to $\nu-\nu$ interactions.

10.Impact of NNLO QED corrections on lepton-proton scattering at MUSE

Authors:T. Engel, F. Hagelstein, M. Rocco, V. Sharkovska, A. Signer, Y. Ulrich

Abstract: We present the complete next-to-next-to-leading order (NNLO) pure pointlike QED corrections to lepton-proton scattering, including three-photon-exchange contributions, and investigate their impact in the case of the MUSE experiment. These corrections are computed with no approximation regarding the energy of the emitted photons and taking into account lepton-mass effects. We contrast the NNLO QED corrections to known next-to-leading order corrections, where we include the elastic two-photon exchange (TPE) through a simple hadronic model calculation with a dipole ansatz for the proton electromagnetic form factors. We show that, in the low-momentum-transfer region accessed by the MUSE experiment, the improvement due to more sophisticated treatments of the TPE, including inelastic TPE, is of similar if not smaller size than some of the NNLO QED corrections. Hence, the latter have to be included in a precision determination of the low-energy proton structure from scattering data, in particular for electron-proton scattering. For muon-proton scattering, the NNLO QED corrections are considerably smaller.

1.Novel approach to measure quark/gluon jets at the LHC

Authors:Petr Baroň, Michael H. Seymour, Andrzej Siódmok

Abstract: In this paper, we present a new proposal on how to measure quark/gluon jet properties at the LHC. The measurement strategy takes advantage of the fact that the LHC has collected data at different energies. Measurements at two or more energies can be combined to yield distributions of any jet property separated into quark and gluon jet samples on a statistical basis, without the need for an independent event-by-event tag. We illustrate our method with a variety of different angularity observables, and discuss how to narrow down the search for the most useful observables.

2.Planar three-loop QCD helicity amplitudes for $V$+jet production at hadron colliders

Authors:Thomas Gehrmann, Petr Jakubčík, Cesare Carlo Mella, Nikolaos Syrrakos, Lorenzo Tancredi

Abstract: We compute the planar three-loop Quantum Chromodynamics (QCD) corrections to the helicity amplitudes involving a vector boson $V=Z,W^\pm,\gamma^*$, two quarks and a gluon. These amplitudes are relevant to vector-boson-plus-jet production at hadron colliders and other precision QCD observables. The planar corrections encompass the leading colour factors $N^3$, $N^2 N_f$, $N N_f^2$ and $N_f^3$. We provide the finite remainders of the independent helicity amplitudes in terms of multiple polylogrithms, continued to all kinematic regions and in a form which is compact and lends itself to efficient numerical evaluation.

3.Updated global fit of the ATHDM with heavy scalars

Authors:Anirban Karan, Víctor Miralles, Antonio Pich

Abstract: An updated global fit on the parameter-space of the Aligned Two-Higgs-Doublet model has been performed with the help of the open-source package \texttt{HEPfit}, assuming the Standard-Model Higgs to be the lightest scalar. No new sources of CP violation, other than the phase in the CKM matrix of the Standard Model, have been considered. A similar global fit was previously performed in Ref. \cite{Eberhardt:2020dat} with a slightly different set of parameters. Our updated fit incorporates improved analyses of the theoretical constraints required for positivity of the scalar potential and perturbative unitarity, additional flavour observables and updated data on direct searches of heavy scalars at the LHC, Higgs signal strengths and electroweak precision observables. Although not included in the main fit, the implications of the CDF measurement of the $W^\pm$ mass are also discussed.

4.About AKM scaling and oscillations in elastic scattering at very small momentum transfer at the LHC

Authors:Per Grafström

Abstract: The ATLAS and TOTEM collaborations have measured the differential elastic cross section at centre-of mass energy $\sqrt{s}$=13 TeV and at small four-moment squared $|t|$. The data at very small $|t|$ i.e. $|t|<0.01GeV^{2}$ have been analysed in terms of so called AKM (Auberson, Kinoshita and Martin) oscillations. An indication of a possible oscillation of this type had previously been reported at $\sqrt{s}$=541 GeV using data from the UA4/2 experiment. There are no such indications in the data at 13 TeV examined here.

5.Tuning Pythia8 for future $e^+e^-$ colliders

Authors:Zhijie Zhao, Mikael Berggren, Jenny List

Abstract: The majority of Monte-Carlo (MC) simulation campaigns for future $e^+e^-$ colliders has so far been based on the leading-order (LO) matrix elements provided by Whizard 1.95, followed by parton shower and hadronization in Pythia6, using the tune of the OPAL experiment at LEP. In this contribution, we test and develop the interface between Whizard3 and Pythia8. As a first step, we simulate the $e^+e^-\to q\bar{q}$ process with LO matrix elements, and compare three tunes in Pythia8: the standard Pythia8 tune, the OPAL tune and the ALEPH tune. At stable-hadron level, predictions of charged and neutral hadron multiplicities of these tunes are compared to LEP data, since they are strongly relevant to the performance of particle flow algorithms. The events are used to perform a full detector simulation and reconstruction of the International Large Detector concept (ILD) as an example for a particle-flow-optimised detector. At reconstruction level, a comparison of the jet energy resolution in these tunes is presented. We found good agreement with previous results that were simulated by Whizard1+Pythia6. In addition, the preliminary next-to-leading order (NLO) results are also presented. This modern MC simulation chain, with matched NLO matrix elements in the future, should be introduced to ILC or other future $e^+e^-$ colliders.

6.Dark matter via Baryogenesis: Affleck-Dine Mechanism in the Minimal Supersymmetric Standard Model

Authors:K. El Bourakadi, M. Ferricha-Alami, Z. Sakhi, M. Bennai, H. Chakir

Abstract: We conducted an investigation into Affleck-Dine baryogenesis within the context of D-term inflation, specifically focusing on its relationship with a recent reheating formalism. It was found that by considering a specific reheating temperature, the observed baryon asymmetry can be accounted through Affleck-Dine baryogenesis. Additionally, the majority of gravitinos are inferred to be generated from the decay of the next-to-lightest supersymmetric particle, with Q-balls potentially serving as a source of gravitinos via NSP decay. The temperature at which decay occurs depends on the charge of the Q-balls, which is determined by the fragmentation of the Affleck-Dine condensate. Remarkably, the gravitino mass required for dark matter aligns naturally with the theoretical gravitino mass.

7.Heavy flavors and quarkonia: highlights, open questions, and perspectives

Authors:Andrea Dubla

Abstract: An overview of the phenomenology and experimental results on open heavy-flavour and quarkonium production in heavy-ion collisions at the RHIC and at the LHC energies is presented, with special emphasis on observables that carry information from the different collision stages. Perspective for future measurements and phenomenological modeling, that will shed light on the current open question in heavy-ion collisions, will be also discussed.

8.Boosting the production of sterile neutrino dark matter with self-interactions

Authors:Maria Dias Astros, Stefan Vogl

Abstract: Sterile neutrinos are well-motivated and simple dark matter (DM) candidates. However, sterile neutrino DM produced through oscillations by the Dodelson-Widrow mechanism is excluded by current $X$-ray observations and bounds from structure formation. One minimal extension, that preserves the attractive features of this scenario, is self-interactions among sterile neutrinos. In this work, we analyze how sterile neutrino self-interactions mediated by a scalar affect the production of keV sterile neutrinos for a wide range of mediator masses. We find four distinct regimes of production characterized by different phenomena, including partial thermalization for low and intermediate masses and resonant production for heavier mediators. We show that significant new regions of parameter space become available which provide a target for future observations.

9.Addendum: Improved MSSM Higgs mass calculation using the 3-loop FlexibleEFTHiggs approach including $x_t$-resummation

Authors:Thomas Kwasnitza, Dominik Stöckinger, Alexander Voigt

Abstract: In this addendum we present the stand-alone C++ program MSSMEFTHiggs3L, which implements the 3-loop FlexibleEFTHiggs approach to calculate the lightest CP-even Higgs boson pole mass in the real MSSM at N$^3$LL and N$^3$LO with $x_q$ resummation, presented in JHEP 07 (2020) 197 (arXiv:2003.04639).

10.Momentum distribution of charm hadrons in a fluid-dynamic approach

Authors:Federica Capellino, Andrea Dubla, Stefan Floerchinger, Eduardo Grossi, Andreas Kirchner, Silvia Masciocchi

Abstract: Exploiting a mapping between transport theory and fluid dynamics, we show how a fluid-dynamic description of the diffusion of charm quarks in the QCD plasma is feasible. We show results for spectra of charmed hadrons obtained with a fluid-dynamic description of the quark-gluon plasma (QGP) coupled with the conservation of a heavy-quark - antiquark current. We compare our calculations with the most recent experimental data in order to provide further constraints on the transport coefficients of the QGP.

11.Distinct photon-ALP propagation modes

Authors:Qing-Hong Cao, Zuowei Liu, Jun-Chen Wang

Abstract: The detection of ultra high energy gamma-rays provides an opportunity to explore the existence of ALPs at the multi-hundred TeV and PeV energy scales. We discover that we can employ analytic methods to investigate the propagation of photon-ALP beams in scenarios where the energy of photons $\omega \geq 100$ TeV. Our analytical calculations uncover the presence of two distinct modes of photon propagation resulting from the interplay between ALP-photon mixing and attenuation effects. Next, we analyze observable quantities such as the degree of polarization and survival probability in these two modes. We determine the conditions under which a significant polarization effect can be observed and identify the corresponding survival probability. Finally, we extend our analytic methods to cover the energy range of $10^{-3}$ to $10^4$ GeV and analyze the influence of ALPs on the experimental signals.

12.Prospects for light Higgs measurements at the 250 GeV ILC

Authors:Aleksander Filip Żarnecki

Abstract: A light Higgs boson, with mass of the order of 100 GeV, is still not excluded by the existing experimental data, provided its coupling to gauge bosons is strongly suppressed compared to a SM-like Higgs boson at the same mass. Also other couplings of such a scalar could be very different from the SM predictions leading to non-standard decay paterns. Considered in the presented study is the feasibility of direct observation of the 96 GeV Higgs boson of N2HDM model with dominant decays to tau lepton pairs.

13.Resonance-aware NLOPS matching for off-shell $t\bar t+tW$ production with semileptonic decays

Authors:Tomáš Ježo, Jonas M. Lindert, Stefano Pozzorini

Abstract: The increasingly high accuracy of top-quark studies at the LHC calls for a theoretical description of $t\bar t$ production and decay in terms of exact matrix elements for the full $2\to 6$ process that includes the off-shell production and the chain decays of $t\bar t$ and $tW$ intermediate states, together with their quantum interference. Corresponding NLO QCD calculations matched to parton showers are available for the case of dileptonic channels and are implemented in the bb4l Monte Carlo generator, which is based on the resonance-aware POWHEG method. In this paper, we present the first NLOPS predictions of this kind for the case of semileptonic channels. In this context, the interplay of off-shell $t\bar t+tW$ production with various other QCD and electroweak subprocesses that yield the same semileptonic final state is discussed in detail. On the technical side, we improve the resonance-aware POWHEG procedure by means of new resonance histories based on matrix elements, which enable a realistic separation of $t\bar t$ and $tW$ contributions. Moreover, we introduce a general approach which makes it possible to avoid certain spurious terms that arise from the perturbative expansion of decay widths in any off-shell higher-order calculation, and which are large enough to jeopardise physical finite-width effects. These methods are implemented in a new version of the bb4l Monte Carlo generator, which is applicable to all dileptonic and semileptonic channels, and can be extended to fully hadronic channels. The presented results include a NLOPS comparison of off-shell against on-shell $t\bar t+tW$ production and decay, where we highlight various non-trivial aspects related to NLO and parton-shower radiation in leptonic and hadronic top decays.

14.Unconventional mechanisms of heavy quark fragmentation

Authors:B. Z. Kopeliovich, J. Nemchik, I. K. Potashnikova, Ivan Schmidt

Abstract: Heavy and light quarks produced in high-$p_T$ partonic collisions radiate differently. Heavy quarks regenerate their color field, stripped-off in the hard reaction, much faster than the light ones and radiate a significantly smaller fraction of the initial quark energy. This peculiar feature of heavy-quark jets leads to a specific shape of the fragmentation functions observed in $e^+e^-$ annihilation. Differently from light flavors, the heavy quark fragmentation function strongly peaks at large fractional momentum $z$, i.e. the produced heavy-light mesons, $B$ or $D$, carry the main fraction of the jet momentum. This is a clear evidence of the dead-cone effect, and of a short production time of a heavy-light mesons. Contrary to propagation of a small $q\bar q$ dipole, which survives in the medium due to color transparency, a heavy-light $Q\bar q$ dipole promptly expands to a large size. Such a big dipole has no chance to remain intact in a dense medium produced in relativistic heavy ion collisions. On the other hand, a breakup of such a dipole does not affect much the production rate of $Q\bar q$ mesons, differently from the case of light $q\bar q$ meson production.

15.Non-decoupling effects from heavy Higgs bosons by matching 2HDM to HEFT amplitudes

Authors:F. Arco, D. Domenech, M. J. Herrero, R. A. Morales

Abstract: In this work we explore the low energy effects induced from the integration of the heavy Higgs boson modes, $H$, $A$ and $H^\pm$, within the Two Higgs Doublet Model (2HDM) by assuming that the lightest Higgs boson $h$ is the one observed experimentally at $m_h \sim 125$ GeV. We work within the context of Effective Field Theories, focusing on the Higgs Effective Field Theory (HEFT), although some comparisons with the Standard Model Effective Field Theory (SMEFT) case are also discussed through this work. Our main focus is placed in the computation of the non-decoupling effects from the heavy Higgs bosons and the capture of such effects by means of the HEFT coefficients which are expressed in terms of the input parameters of the 2HDM. Our approach to solve this issue is by matching the amplitudes of the 2HDM and the HEFT for physical processes involving the light Higgs boson $h$ in the external legs, instead of the most frequently used matching procedure at the Lagrangian level. More concretely, we perform the matching at the amplitudes level for the following physical processes, including scattering and decays: $h\to WW^*\to Wf\bar{f'}$, $h\to ZZ^*\to Zf\bar{f}$, $WW \to hh$, $ZZ \to hh$, $hh \to hh$, $h \to \gamma \gamma$ and $h \to \gamma Z$. One important point of this work is that the matching is required to happen at low energies compared to the heavy Higgs boson masses, and these are heavier than the other particle masses. The proper expansion for this heavy mass limit is also defined here, which provides the results for the non-decoupling effects presented in this work. We finally discuss the implications of the resulting effective coefficients, and remark on the interesting correlations detected among them.

1.T-Model Higgs Inflation in Supergravity

Authors:C. Pallis

Abstract: We focus on a simple, natural and predictive T model of inflation in Supergravity employing as inflaton the Higgs field which leads to the spontaneous breaking of a U(1)_(B-L) symmetry at the SUSY GUT scale. We use a renormalizable superpotential, fixed by a U(1) R symmetry, and a Kahler potential which parameterizes the Kahler manifold SU(2,1)/(SU(2)xU(1))x(SU(2)/U(1)) with scalar curvature R_K=-6/N+2/N_0 where 0<N_0<6. The spectral index ns turns out to be close to its present central observational value and the tensor-to-scalar ratio r increases with N<36. The model can be nicely linked to MSSM offering an explanation of the magnitude of the mu parameter consistently with phenomenological data. It also allows for baryogenesis via non-thermal leptogenesis with gravitino as light as 1 TeV.

2.Possible formation of Quark-Gluon Plasma in small collision systems at the Large Hadron Collider: Observations and Challenges

Authors:Raghunath Sahoo

Abstract: With the advent of unprecedented collision energy at the Large Hadron Collider, CERN, Geneva, a new domain of particle production and possible formation of Quark-Gluon Plasma (QGP) in high-multiplicity proton-proton collisions and the collisions of light nuclei has been a much-discussed topic recently. In this review, I discuss some of the recent observations leading to such a possibility, associated challenges, and some predictions for the upcoming light-nuclei collisions at the LHC.

3.Two-particle angular correlations in the search for new physics at future $e^+e^-$ colliders

Authors:E. Musumeci IFIC, Universitat de València and CSIC, Paterna, R. Perez-Ramos DRII-IPSA, Ivry-sur-Seine, France Laboratoire de Physique Théorique et Hautes Energies, A. Irles IFIC, Universitat de València and CSIC, Paterna, I. Corredoira Instituto Galego de Física de Altas Enerxìas, V. A. Mitsou IFIC, Universitat de València and CSIC, Paterna, E. Sarkisyan-Grinbaum Experimental Physics Department, CERN, Geneva, Switzerland Department of Physics, The University of Texas at Arlington, Arlington, TX USA, M. A. Sanchis-Lozano IFIC, Universitat de València and CSIC, Paterna

Abstract: The analysis of angular particle correlations can yield valuable insights into the initial state of matter in high-energy collisions, thereby potentially revealing the existence of Beyond the Standard Model scenarios such as Hidden Valley (HV). In this study, we focus on a QCD-like hidden sector with relatively massive HV quarks ($\lesssim 100$~GeV) which might enlarge and strengthen azimuthal correlations of final-state SM hadrons. In particular, we study the formation and possible observation of \textit{ridge-like} structures in the angular two-particle correlation function at future $e^+e^-$ colliders, with a much cleaner environment than in hadron colliders, such as the LHC.

4.Cosmological Consequences of Kinetic Mixing between Photon and Dark Photon

Authors:Sung Mook Lee, Dong Woo Kang, Jinn-Ouk Gong, Donghui Jeong, Dong-Won Jung, Seong Chan Park

Abstract: We study the kinetic mixing between the cosmic microwave background (CMB) photon and the birefringent dark photon as a source of cosmic birefringence. We show that indeed the birefringence of the dark photon propagates to the CMB photon, but the resulting birefringence may not be uniform over the sky. Moreover, our investigation sheds light on the essential role played by kinetic mixing in the generation of two fundamental characteristics of the CMB: circular polarization and spectral distortion.

5.BSM patterns in scalar-sector coupling modifiers

Authors:Christoph Englert, Wrishik Naskar, Dave Sutherland

Abstract: We consider what multiple Higgs interactions may yet reveal about the scalar sector. We estimate the sensitivity of a Feynman topology-templated analysis of weak boson Higgs pair production at present and future colliders - where the signal is a function of the Higgs coupling modifiers $\kappa_V$, $\kappa_{2V}$, and $\kappa_\lambda$. While measurements are statistically limited at the LHC, they are under general perturbative control at present and future colliders, departures from the SM expectation give rise to a significant future potential for BSM discrimination in $\kappa_{2V}$. We explore the landscape of BSM models in the space of deviations in $\kappa_V$, $\kappa_{2V}$, and $\kappa_\lambda$, highlighting models that have measurable order-of-magnitude enhancements in either $\kappa_{2V}$ or $\kappa_\lambda$, relative to their deviation in the single Higgs coupling $\kappa_V$.

6.Fate of homogeneous $Z_2$-symmetric scalar condensates

Authors:Wen-Yuan Ai, Zi-Liang Wang

Abstract: Dark Matter, if represented by a $Z_2$-symmetric scalar field, can manifest as both particles and condensates. In this paper, we study the evolution of an oscillating homogeneous condensate of a $Z_2$-symmetric scalar field in a thermal plasma in an FLRW universe. We focus on the perturbative regime where the oscillation amplitude is sufficiently small so that parametric resonance is inefficient. This perturbative regime necessarily comprises the late stage of the condensate decay and determines its fate. The coupled coarse-grained equations of motion for the condensate, radiation, and spacetime are derived from first principles using nonequilibrium quantum field theory. We obtain analytical expressions for the relevant microscopic quantities that enter the equations of motion and solve the latter numerically. We find that there is always a nonvanishing relic abundance for a $Z_2$-symmetric condensate because its decay rate decreases faster than the Hubble parameter at late times due to either the amplitude-dependence or the temperature-dependence in the condensate decay rate. Consequently, accounting for the condensate contribution to the overall Dark Matter relic density is essential for $Z_2$ scalar singlet Dark Matter. Unlike normal thermal freeze-out for particles, the condensate relic density depends on the initial condition which we take as arbitrary in the present work provided that it falls within the perturbative regime.

7.The study of the nonleptonic decay $Ξ^0_c \to Λ^+_c π^-$ in the covariant confined quark model

Authors:Mikhail A. Ivanov, Valery E. Lyubovitskij, Zhomart Tyulemissov

Abstract: The nonleptonic decay $\Xi^0_c \to \Lambda^+_c \pi^-$ with $\Delta C=0$ is systematically studied in the framework of the covariant confined quark model (CCQM) with account for both short and long distance effects. The short distance effects are induced by four topologies of external and internal weak $W^\pm$ exchange, while long distance effects are saturated by an inclusion of the so-called pole diagrams with an intermediate $\frac12^+$ and $\frac12^-$ baryon resonances. The contributions from $\frac12^+$~resonances are calculated straightforwardly by account for single charmed $\Sigma^0_c$ and $\Xi^{'\,+}_c$~baryons whereas the contributions from $\frac12^-$~resonances are calculated by using the well-known soft-pion theorem in the current-algebra approach. It allows to express the parity-violating S-wave amplitude in terms of parity-conserving matrix elements. It is found that the contribution of external and internal $W$-exchange diagrams is significantly suppressed by more than one order of magnitude in comparison with data. The pole diagrams play the major role to get consistency with experiment.

8.Search for Light Dark Matter with accelerator and direct detection experiments: comparison and complementarity of recent results

Authors:S. ~N. ~Gninenko, D. ~V. ~Kirpichnikov, N. ~V. ~Krasnikov

Abstract: We discuss the most sensitive constraints on Light Dark Matter (LDM) from accelerator experiments NA64 and BaBar and compare it with recent results from direct searches at XENON1T, DAMIC-M, SuperCDMS, and DarkSide-50. We show that for the dark photon ($A'$) model with scalar LDM, NA64 gives more stringent bounds for $A'$ masses $m_{A'} \leq 0.15~GeV$ than direct searches. Moreover, for the case of Majorana LDM the damping DM velocity $v$ factor, $v^2 \sim O(10^{-6})$, for the elastic LDM electron(nucleon) cross section makes direct observation of Majorana LDM extremely challenging, while the absence of this suppression in the NA64 case gives an advantage to the experiment. The similar situation takes place for pseudo-Dirac LDM. The BaBar provides the most stringent bounds for $A'$ masses $m_{A'} \geq 0.35~GeV$. For scalar LDM the direct detection experiments give more stringent bounds at $m_{A'} \geq 0.35~GeV$ while for Majorana and pseudo-Dirac LDM case, the BaBar bounds are more stringent. The complementarity of the two approaches in searching for LDM is underlined.

9.Parity Solution to the Strong CP Problem and a Unified Framework for Inflation, Baryogenesis, and Dark Matter

Authors:K. S. Babu, Rabindra N. Mohapatra, Nobuchika Okada

Abstract: It has been known for some time that asymptotic parity invariance of weak interactions can provide a solution to the strong CP problem without the need for the axion. Left-right symmetric theories which employ a minimal Higgs sector consisting of a left-handed and a right-handed doublet is an example of such a theory wherein all fermion masses arise through a generalized seesaw mechanism. In this paper we present a way to understand the origin of matter-antimatter asymmetry as well as the dark matter content of the universe in these theories using the Affleck-Dine (AD) leptogenesis mechanism and inflaton decay, respectively. Three gauge singlet fermions are needed for this purpose, two of which help to implement the Dirac seesaw for neutrino masses while the third one becomes the non-thermal warm dark matter candidate. A soft lepton number breaking term involving the AD scalar field is used to generate lepton asymmetry which suffers no wash-out effects and maintains the Dirac nature of neutrinos. This framework thus provides a unified description of many of the unresolved puzzles of the standard model that require new physics.

10.Multicomponent Scalar Dark Matter with an Extended Gauge Sector

Authors:Baradhwaj Coleppa, Kousik Loho, Agnivo Sarkar

Abstract: We consider an extension of the Standard Model of particle physics with an additional $SU(2)$ gauge sector along with an additional scalar bidoublet and a non-linear sigma field. The neutral components of the bidoublet serve as dark matter candidates by virtue of the bidoublet being odd under a $Z_2$ symmetry. Generic beyond Standard Model constraints like vacuum stability, invisible decay of higgs, Higgs alignment limit and collider constraints on heavy gauge bosons restrict the parameter space of this model. In this multicomponent dark matter scenario, we investigate the interplay between the annihilation and co-annihilation channels originating from the new gauge sector as those contribute to the relic abundance. We also inspect the direct detection constraints on scattering cross-sections of the dark matter particles with the detector nucleons and present our observations.

11.Gravitational form factors of $Δ$ baryon via QCD sum rules

Authors:Z. Dehghan, K. Azizi, U. Özdem

Abstract: The gravitational form factors of a hadron are defined through the matrix elements of the energy-momentum tensor current, which can be decomposed into the quark and gluonic parts, between the hadronic states. These form factors provide important information for answering fundamental questions about the distribution of the energy, the spin, the pressure and the shear forces inside the hadrons. Theoretical and experimental studies of these form factors provide exciting insights on the inner structure and geometric shapes of hadrons. Inspired by this, the gravitational form factors of $\Delta$ resonance are calculated by employing the QCD sum rule approach. The acquired gravitational form factors are used to calculate the composite gravitational form factors like the energy and angular momentum multipole form factors, D-terms related to the mechanical properties like the internal pressure and shear forces as well as the mass radius of the system. The predictions are compared with the existing results in the literature.

12.New observables for testing Bell inequalities in $W$ boson pair production

Authors:Qi Bi, Qing-Hong Cao, Kun Cheng, Hao Zhang

Abstract: We show that testing Bell inequalities in $W^\pm$ pair systems by measuring their angular correlation suffers from the ambiguity in kinetical reconstruction of the di-lepton decay mode. We further propose a new set of Bell observables based on the measurement of the linear polarization of the $W$ bosons, providing a realistic observable to test Bell inequalities in $W^\pm$ pair systems for the first time.

13.New developments on the WHIZARD event generator

Authors:Jürgen Reuter, Pia Bredt, Wolfgang Kilian, Maximilian Löschner, Krzysztof Mękała, Thorsten Ohl, Tobias Striegl, Aleksander Filip Żarnecki

Abstract: We give a status report on new developments in the WHIZARD event generator, including NLO electroweak automation for $e^+e^-$ colliders, loop-induced processes, POWHEG matching, new features in the UFO interface and the current development for matching between exclusive photon radiation and fixed-order LO/NLO electroweak (EW) corrections. We report on several bug fixes relevant for certain aspects of the ILC250 Monte Carlo (MC) mass production, especially on the normalization of matching EPA samples with full-matrix element samples. Finally, we mention some ongoing work on efficiency improvements regarding parallelization of matrix elements and phase space sampling, as well as plans to revive the top threshold simulation.

14.Contribution of hadronic light-by-light scattering to the hyperfine structure of muonium

Authors:V. I. Korobov BLTP JINR, A. V. Eskin Samara University, A. P. Martynenko Samara University, F. A. Martynenko Samara University

Abstract: The contribution of hadronic scattering of light-by-light to the hyperfine structure of muonium is calculated using experimental data on the transition form factors of two photons into a hadron. The amplitudes of interaction between a muon and an electron with horizontal and vertical exchange are constructed. The contributions due to the exchange of pseudoscalar, axial vector, scalar and tensor mesons are taken into account.

15.Single inclusive particle production at next-to-leading order in proton-nucleus collisions at forward rapidities: hybrid approach meets TMD factorization

Authors:Tolga Altinoluk, Néstor Armesto, Alexander Kovner, Michael Lublinsky

Abstract: We revisit the calculation of the cross section for forward inclusive single hadron production in $pA$ collisions within the hybrid approach. We show that the proper framework to perform this calculation beyond leading order is not the collinear factorization, as has been assumed so far, but the TMD factorized framework. Within the TMD factorized approach we show that all the large transverse logarithms appearing in the fixed order calculation, are resummed into the evolution of the TMD PDFs and TMD FFs with factorization scale. The resulting expressions, when written in terms of TMDs evolved to the appropriate, physically well understood factorization scale, contain no additional large logarithms. The absence of any large logarithms in the resummed result should ensure positivity of the cross section and eradicate the persistent problem that have plagued the previous attempts at calculating this observable in the hybrid approach.

16.Modular binary octahedral symmetry for flavor structure of Standard Model

Authors:Gui-Jun Ding, Xiang-Gan Liu, Jun-Nan Lu, Ming-Hua Weng

Abstract: We have investigated the modular binary octahedral group $2O$ as a flavor symmetry to explain the structure of Standard Model. The vector-valued modular forms in all irreducible representations of this group are constructed. We have classified all possible fermion masses models based on the modular binary octahedral group $2O$. A comprehensive numerical analysis is performed, and we present some benchmark quark/lepton masses models in well agreement with the experimental data. Notably we find a minimal modular invariant model for leptons and quarks, which is able to explain simultaneously the masses and mixing parameters of both quarks and leptons in terms of 14 real free parameters including the modulus $\tau$. The fermion mass hierarchies around the vicinity of the modular fixed points are explored.

17.Probing an ultralight QCD axion with electromagnetic quadratic interaction

Authors:Hyungjin Kim, Alessandro Lenoci, Gilad Perez, Wolfram Ratzinger

Abstract: The axion-gluon coupling is the defining feature of the QCD axion. This feature induces additional and qualitatively different interactions of the axion with standard model particles -- quadratic couplings. Previously, hadronic quadratic couplings have been studied and experimental implications have been explored especially in the context of atomic spectroscopy and interferometry. We investigate additional quadratic couplings to the electromagnetic field and electron mass. These electromagnetic quadratic couplings are generated at the loop level from threshold corrections and are expected to be present in the absence of fine-tuning. While they are generally loop-suppressed compared to the hadronic ones, they open up new ways to search for the QCD axion, for instance via optical atomic clocks. Moreover, due to the velocity spread of the dark matter field, the quadratic nature of the coupling leads to low-frequency fluctuations in any detector setup. These distinctive low-frequency fluctuations offer a way to search for heavier axions. We provide an analytic expression for the power spectral density of this low-frequency background and briefly discuss experimental strategies for a low-frequency background search.

18.Exploring Freeze-out and Freeze-in Dark Matter via Effective Froggatt-Nielsen Theory

Authors:Rusa Mandal, Tom Tong

Abstract: Motivated by the dynamical reasons for the hierarchical structure of the Yukawa sector of the Standard Model (SM), we consider an extension of the SM with a complex scalar field, known as `flavon', based on the Froggatt-Nielsen mechanism. In an effective theory approach, the SM fermion masses and mixing patterns are generated in orders of the parameter related to the vacuum expectation value of the flavon field and the cut-off of the effective theory. By introducing right-handed neutrinos, we study the viability of the lightest right-handed neutrino as a dark matter candidate, where the same flavon field acts as a mediator between the dark and the SM sectors. We find that dark matter genesis is achieved both through freeze-out and freeze-in mechanisms encompassing the $\mathcal{O}(\text{GeV})$ -- $\mathcal{O}(\text{TeV})$ mass range of the mediator and the dark matter particle. In addition to tree-level spin-dependent cross section, the model gives rise to tree- and loop-level contributions to spin-independent scattering cross section at the direct detection experiments such as XENON and LUX-ZEPLIN which can be probed in their future upgrades. By choosing suitable Froggatt-Nielsen charges for the fermions, we also generate the mass spectrum of the SM neutrinos via the Type-I seesaw mechanism. Flavor-changing neutral current processes, such as radiative lepton decay, meson mixing, and top-quark decay remain the most constraining channels and provide testability for this minimal setup that addresses several major shortcomings of the SM.

19.Leading two-loop corrections to the Higgs di-photon decay in the Inert Doublet Model

Authors:Masashi Aiko, Johannes Braathen, Shinya Kanemura

Abstract: Leading two-loop contributions to the di-photon decay of the Higgs boson are evaluated for the first time in the Inert Doublet Model (IDM). We employ for this calculation the Higgs low-energy theorem, meaning that we obtain corrections to the Higgs decay process by taking Higgs-field derivatives of the leading two-loop contributions to the photon self-energy. Specifically, we have included purely scalar corrections involving inert BSM Higgs bosons, as well as external-leg contributions involving both the inert scalars and fermions. Our calculation has been performed with a full on-shell renormalization, and in the gauge-less limit. We investigate our results numerically in two scenarios of the IDM: one with a light dark matter (DM) candidate (Higgs resonance scenario), and another with all additional scalars heavy (heavy Higgs scenario). In both cases, we find that the inclusion of two-loop corrections qualitatively modifies the behavior of the decay width, compared with the one-loop ($i.e.$ leading) order, and that they increase the deviation from the Standard Model. These large deviations can be tested at the High-Luminosity LHC.

20.Renormalized equations of motions for scalars and fermions in the 2PI formalism

Authors:A. Banik, H. Hinrichsen, W. Porod

Abstract: We present on shell-scheme for the 2PI formalism with a particular focus on the renormalized equations of motion. We first revisit the so-called Hartree approximation where we give the counterterms for both the broken and unbroken phase. Moreover, we give explicit formulas for the renormalized three- and four-point functions in the broken phase. We then turn to the sunset approximation, with only scalars and then including fermions. We give explicit formulas for the wavefunction and mass counterterms. Moreover, we show that, in particular, the two-point functions can be obtained numerically in a fast converging scheme even for large couplings of order one.

21.A general algorithm to build mixed real and virtual antenna functions for higher-order calculations

Authors:Oscar Braun-White, Nigel Glover, Christian T Preuss

Abstract: The antenna-subtraction technique has demonstrated remarkable effectiveness in providing next-to-next-to-leading order in $\alpha_s$ (NNLO) predictions for a wide range of processes relevant for the Large Hadron Collider. In a previous paper [1], we demonstrated how to build real-radiation antenna functions for any number of real emissions directly from a specified list of unresolved limits. Here, we extend this procedure to the mixed case of real and virtual radiation, for any number of real and virtual emissions. A novel feature of the algorithm is the requirement to match the antenna constructed with the correct unresolved limits to the other elements of the subtraction scheme. We discuss how this can be achieved and provide a full set of real-virtual NNLO antenna functions (together with their integration over the final-final unresolved phase space). We demonstrate that these antennae can be combined with the real-radiation antennae of Ref. [1] to form a consistent NNLO subtraction scheme that cancels all explicit and implicit singularities at NNLO. We anticipate that the improved antenna functions should be more amenable to automation, thereby making the construction of subtraction terms for more complicated processes simpler at NNLO.

22.Role of QCD in moduli stabilization during inflation and axion dark matter

Authors:Ryuichiro Kitano, Motoo Suzuki, Wen Yin

Abstract: Ignorance of the initial condition for the axion dynamics in the early Universe has led us to consider an $O(1)$ valued initial amplitude, and that prefers the decay constant, $F_a$, of the QCD axion to be an intermediate scale such as $10^{12}$ GeV in order to explain the dark matter abundance. We explore a cosmological scenario of $F_a$ being much larger than $10^{12}$ GeV by considering the axion and moduli dynamics during inflation to set the initial amplitude. We show that if the volume moduli (radion) of the extra-dimension is stabilized mainly by the QCD contribution to the moduli potential during inflation, the QCD axion with the string-scale decay constant obtains a mass around the inflationary Hubble parameter. This means that the axion rolls down to the $\theta = 0$ minimum during the inflation realizing almost vanishing initial amplitude, and the inflationary quantum fluctuation can be the dominant source of the current number density of axions. We find natural parameter regions where the axion explains the cold dark matter of the Universe, while the constraint on the isocurvature perturbation is avoided. The presence of the axion miniclusters or axion stars are predicted in a wide range of parameters, including the one explains the Subaru-HCS microlensing event.

1.$N_{\rm eff}$ constraints on light mediators coupled to neutrinos: the dilution-resistant effect

Authors:Shao-Ping Li, Xun-Jie Xu

Abstract: We investigate the impact of new light particles, carrying significant energy in the early universe after neutrino decoupling, on the cosmological effective relativistic neutrino species, $N_{{\rm eff}}$. If the light particles are produced from decoupled neutrinos, $N_{{\rm eff}}$ is predominantly modified through the dilution-resistant effect. This effect arises because the energy stored in the mass of new particles is less diluted than the photon and neutrino energy as the universe expands. Our study comprehensively explores this effect, deriving $N_{{\rm eff}}$ constraints on the couplings of light mediators with neutrinos, encompassing both scalar and vector mediators. We find that the dilution-resistant effect can increase $N_{{\rm eff}}$ by 0.118 and 0.242 for scalar and vector mediators, respectively. These values can be readily reached by forthcoming CMB experiments. Upon reaching these levels, future $N_{{\rm eff}}$ constraints on the couplings will be improved by many orders of magnitude.

2.Intergenerational gauged $B-L$ model and its implication to muon $g-2$ anomaly and thermal dark matter

Authors:Nobuchika Okada, Osamu Seto

Abstract: We study the flavor dependent $U(1)_{B_i-L_j}$ models, where an $i$-th generation of quarks and $j(\neq i)$-th generation of leptons are charged. By solving the anomaly free condition for the matter sector of the SM fermions and three generations of RH neutrinos, we find that the $j$-th generation of RH neutrino is not necessarily charged under the $U(1)_{B_i-L_j}$ gauge symmetry with the charge $-1$ and the other (neither $i$-th nor $j$-th) generation of RH neutrino can also be. As a general solution for the anomaly cancellation conditions, the other two RN neutrinos than the charge $-1$ RH neutrino may have non-vanishing charge and be stable due to the gauge invariance, and hence it is a candidate for dark matter (DM) in our Universe. We apply this result to a $B_3-L_2$ model and consider a light thermal DM and a solution to the muon $g-2$ anomaly. We identify the parameter region to have the DM mass range from MeV to sub-GeV and simultaneously solve the muon $g-2$ anomaly. We also derive the constraints on the gauge kinetic mixing parameter by using the latest Borexino Phase-II data.

3.Observability of Parameter Space for Charged Higgs Boson in its bosonic decays in Two Higgs Doublet Model Type-1

Authors:Ijaz Ahmed, Waqas Ahmad, M. S. Amjad

Abstract: This study explores the possibility of discovering $H^{\pm}$ through its bosonic decays, i.e. $H^{\pm}\rightarrow W^\pm\phi$ (where $\phi$ = h or A), within the Type-I Two Higgs Doublet Model (2HDM). The main objective is to demonstrate the available parameter space after applying the recent experimental and theoretical exclusion limits. We suggest that for $m_{H^\pm}$ = 150 GeV is the most probable mass for the $H^\pm\rightarrow W^\pm\phi$ decay channel in $pp$ collisions at $\sqrt{s}$ = 8, 13 and 14 TeV. Therefore we propose that this channel may be used as an alternative to $H^\pm\rightarrow \tau^\pm\nu$.

4.Cancellation of small-x divergences in the three-gluon-vertex Hamiltonian with canonical gluon mass

Authors:Juan José Gálvez-Viruet, María Gómez-Rocha

Abstract: The front form of Hamiltonian dynamics provides a framework within QCD in which interaction terms are invariant under 7 of 10 Poincar\'e transformations and the vacuum structure is simple. However, canonical expressions are divergent and must be regulated before attempting to define an eigenvalue problem. The renormalization group procedure for effective particles (RGPEP) provides a systematic way of renormalizing Hamiltonians and obtaining counterterms. One of its achievements is the description of asymptotic freedom with a running coupling defined as the coefficient of the three-gluon-vertex operators in the renormalized Hamiltonian. Yet, the results we obtain need a deeper understanding since the coefficient function shows a finite cutoff dependence, at least in the third-order terms of the perturbative expansion. In this work, we present an RGPEP computation of the three-gluon vertex with a different regularization scheme based on massive gluons. Our calculation shows that the three-gluon Hamiltonian interaction term has a finite limit as the gluon mass vanishes, but the finite function $h(x)$ that was obtained in previous calculations as a consequence of the finite dependence on the regularization is different. This result indicates a need for understanding how to eliminate finite regularization effects from Hamiltonians for effective quarks and gluons in QCD. Nevertheless, it is remarkable that all terms depending on the gluon mass cancel out in the limit of vanishing gluon mass in a non trivial way, even when each term individually diverges in such limit.


Authors:Maximilian Berbig

Abstract: The family of Dirac Seesaw models offers an intriguing alternative explanation for the smallness of neutrino masses without necessarily requiring microscopic lepton number violation, when compared to the more familiar class of Majorana Seesaws. A global $\text{U}(1)_\text{D}$ symmetry, that is explicitly broken by a higher dimensional scalar operator, ensures that the right handed neutrino does not couple directly to the Standard Model like Higgs and an exact gauged or residual lepton number symmetry prohibits all Majorana masses. We demonstrate that all three Dirac Seesaws possess a Pseudo-Nambu-Goldstone boson associated with the $\text{U}(1)_\text{D}$ symmetry, that we call the Diraxion, whose cosmological dynamics have so far been left unexplored. Furthermore we illustrate that a Dirac-Leptogenesis version of the recently proposed Lepto-Axiogenesis scenario can be realized in this class of models, leading to a unified origin of the observed baryon asymmetry and dark matter relic abundance. Explaining only the baryon asymmetry can lead to potentially observable amounts of right handed neutrino dark radiation with $\Delta N_\text{eff.}\lesssim 0.028$. On the other hand, if we only fix the dark matter abundance via the kinetic misalignment mechanism, this set-up could lead to detectable signatures in proposed cosmic neutrino background experiments via decays of eV-scale Diraxions to neutrinos. Here there is no domain wall problem, since topological defects immediately decay to a subleading fraction of relic Diraxions. A key ingredient of all Axiogenesis scenarios is the dynamics of relatively light scalar called the Saxion, that in our case has a mass at the GeV-scale and which might reveal itself in heavy meson decays or collider searches. Our setup predicts isocurvature perturbations in baryons, dark matter and dark radiation sourced by fluctuations of the Saxion.

6.LHC tau-pair production constraints on $a_τ$ and $d_τ$

Authors:Ulrich Haisch, Luc Schnell, Joachim Weiss

Abstract: We point out that relevant constraints on the anomalous magnetic ($a_\tau$) and electric ($d_\tau$) moment of the tau lepton can be derived from tau-pair production measurements performed at the LHC. Our conclusion is based on the observation that the leading relative deviations from the Standard Model prediction for $pp \to \tau^+ \tau^-$ due to $a_\tau$ and $d_\tau$ are enhanced at high energies. Less precise measurements at hadron colliders can therefore offer the same or better sensitivity to new physics with respect to high-precision low-energy measurements performed at lepton machines. We derive bounds on $a_\tau$ and $d_\tau$ using the full LHC Run II data set on tau-pair production and compare our findings with the current best limits on the tau anomalous moments.

7.Wigner and Husimi partonic distributions of the pion in a chiral quark model

Authors:Wojciech Broniowski, Enrique Ruiz Arriola

Abstract: Generalized transverse momentum distributions (GTMDs), the Wigner, and the Husimi distributions of quarks in the pion are evaluated in a chiral quark model at the one-loop-level. Analytic expressions are obtained for GTMDs, allowing for a qualitative discussion of their features, whereas the Wigner and the Husimi distribution are obtained with numerical integration of simple formulas. We explain the features of the Wigner distributions, in particular their non-positivity. In our model, the Husimi distributions, which are interpreted as coarse-grained Wigner distributions, are not mathematically positive-definite, but the magnitude of their negative values is tiny and occurs at large transverse momenta and impact parameters. Hence, as expected, coarse-graining leads to better behaved functions from the point of view of the probabilistic interpretation.

8.On the Positronium g-factor

Authors:J. Agil, D. Bakalov, R. Battesti, C. Rizzo

Abstract: In this letter, we recall the main facts concerning the g-factor of positronium and we show how the value of the g-factor of the positronium is important. Taking it better into consideration may provide a solution to the reported discrepancy between QED theory and experiment concerning the hyperfine splitting of the fundamental level of the positronium. We also give the only experimental value that existing experiment can provide $g_{pos}=2.0023\pm 0.0012$.

9.Refactorization of endpoint divergencies for the ${\cal O}_7$ contribution to $\bar B_s \to μ^+μ^-$

Authors:Nicolas Seitz

Abstract: We report on the construction of a factorization theorem for the contribution of the electromagnetic dipole operator ${\cal O}_7$ to the $\bar B_s \to \mu^+\mu^-$ decay amplitude. The leading-order contribution from a QED box diagram features a double-logarithmic enhancement associated to the different rapidities of the light quark in the $\bar B_s$-meson and the energetic muons in the final state. We analyse the cancellation of the related endpoint divergences appearing in individual momentum regions, and show how the rapidity logarithms can be isolated by suitable subtractions applied to the corresponding bare factorization theorem. This allows us to include in a straightforward manner the QCD corrections arising from the renormalization-group running of the hard matching coefficient, the hard-collinear scattering kernel, and the $\bar B_s$-meson distribution amplitude.

10.Prediction of various observables for $B_s^0 \to D_s^{(*)-}\ell^+ν_\ell$ within covariant confined quark model

Authors:J. N. Pandya, P. Santorelli, N. R. Soni

Abstract: In 2020, the LHCb collaboration reported the exclusive branching fractions for the channels $B_s^0 \to D_s^{(*)-}\mu^+\nu_\mu$ for the very first time. In view of these observations, we have recently reported the form factors and branching fraction computations for these channels employing the covariant confined quark model. As different other channels corresponding to $b \to c \ell \nu_\ell$ have provided the hint for New Physics, the analysis of observables such as forward-backward asymmetry, longitudinal and transverse polarizations across the lepton flavours can serve as one of the important probes for the search for possible New Physics. In present work, we compute these observables for all the lepton flavours and compare our predictions with the other theoretical approaches.

11.A primer on Higgs Effective Field Theory with Geometry

Authors:Rodrigo Alonso

Abstract: These lecture notes, prepared for the 2022 QUC summer school at KIAS, provide an introduction to Higgs Effective Field Theory and the use of field geometry in Quantum Field Theory. While not sounding the depths of any of these topics, we will cover and give a sense of the inner workings of: the action for Goldstone bosons, the independence of scattering amplitudes from field parametrisations, linear vs non-linear realizations --their `geography' and experimental prospects to tell them apart--, ultra-violet completions and the LSZ formula for fields in curved space.

1.Models and Potentials in Hadron Spectroscopy

Authors:Sreelakshmi M, Akhilesh Ranjan

Abstract: In the past twenty years, hadron spectroscopy has made immense progress. Experimental facilities have observed different multiquark states during these years. There are different models and phenomenological potentials to study the nature of interquark interaction. In this work, we have reviewed different quark potentials and models used in hadron spectroscopy.

2.Regge Trajectories of Tetraquarks and Pentaquarks with Massive Quarks in the Flux Tube Model

Authors:Sindhu D G, Akhilesh Ranjan, Hemwati Nandan

Abstract: In recent years, many tetraquarks and pentaquarks have been discovered by various experimental groups and X(3872), Zc(3900), X(4430), P + c (4312), P + c (4457) are some of the interesting observed tetraquark and pentaquark states. The Regge trajectories of some such states are studied in view of the flux tube model of hadrons with finite quark masses. The effect of flux tube (or string) length variation on the Regge trajectories of these sates is analysed in detail. It is observed that for a fixed angular momentum, the string length has a constant value. Some other states are also proposed and the results obtained are then compared with the studies by others. Our findings correspond rather well with those of other researchers and with those of the experiment.

3.Soft-Photon Theorem for Pion-Proton Scattering: Next to Leading Term

Authors:Piotr Lebiedowicz, Otto Nachtmann, Antoni Szczurek

Abstract: We investigate the photon emission in pion-proton scattering in the soft-photon limit where the photon energy $\omega \to 0$. The expansion of the $\pi^{\pm} p \to \pi^{\pm} p \gamma$ amplitudes, satisfying the energy-momentum relations, to the orders $\omega^{-1}$ and $\omega^{0}$ is derived. We show that these terms can be expressed completely in terms of the on-shell amplitudes for $\pi^{\pm} p \to \pi^{\pm} p$ and their partial derivatives with respect to $s$ and $t$. The term of order $\omega^{-1}$ is standard, while our term of order $\omega^{0}$ is new. The structure term which is non singular for $\omega \to 0$ is determined to the order $\omega^{0}$ from the gauge-invariance constraint using the generalized Ward identities for pions and the proton.

4.Endpoint behavior of distribution amplitudes of pion and longitudinally polarized rho meson under the influence of renormalon-chain contributions

Authors:S. V. Mikhailov, N. Volchanskiy

Abstract: We calculate two-point massless QCD correlator of nonlocal (composite) vector quark currents with chains of fermion one-loop radiative corrections inserted into gluon lines. The correlator depends on the Bjorken fraction $x$ related to the composite current and, under large-$\beta_0$ approximation, gives the main contributions in each order of perturbation theory. In the mentioned approximation, these contributions dominate the endpoint behavior of the leading-twist distribution amplitudes of light mesons in the framework of QCD sum rules. Based on this, we analyze the endpoint behavior of these distribution amplitudes for $\pi$ and longitudinally polarized $\rho^\|$ mesons and find inequalities for their moments.

5.Flavor-dependent $U(1)$ extension inspired by lepton, baryon and color numbers

Authors:Duong Van Loi, Phung Van Dong

Abstract: There is no reason why the gauge symmetry extension is family universal as in the standard model and the most well-motivated models, e.g. left-right symmetry and grand unification. Hence, we propose a simplest extension of the standard model -- a flavor-dependent $U(1)$ gauge symmetry -- and find the new physics insight. For this aim, the $U(1)$ charge, called $X$, is expressed as $X=x B+y L$ in which $x$ and $y$ are free parameters as functions of flavor index, e.g. for a flavor $i$ they take $x_i$ and $y_i$ respectively, where $B$ and $L$ denote normal baryon and lepton numbers. Imposing a relation involved by the color number $3$, i.e. $-x_{1,2,\cdots,n}=x_{n+1,n+2,\cdots,n+m}=3y_{1,2,\cdots,n+m}\equiv 3z$, for arbitrarily nonzero $z$, we achieve a novel $U(1)$ theory with implied $X$-charge. This theory not only explains the origin of the number of observed fermion families but also offers a possible solution for both neutrino mass and dark matter, which differs from $B-L$ extension. Two typical models based on this idea are examined, yielding interesting results for flavor-changing neutral currents and particle colliders, besides those of neutrino mass and dark matter.

6.Entanglement and Bell inequalities violation in $H\to ZZ$ with anomalous coupling

Authors:Alexander Bernal, Paweł Caban, Jakub Rembieliński

Abstract: We discuss entanglement and violation of Bell-type inequalities for a system of two $Z$ bosons produced in Higgs decays. We take into account beyond the Standard Model (anomalous) coupling between $H$ and daughter bosons but we limit ourselves to an overall scalar $ZZ$ state (we exclude the possibility that $H$ contains a pseudo-scalar component). In particular we consider the case when each $Z$ decays further into fermion-antifermion pair. We find that a $ZZ$ state is entangled and violates the CGLMP inequality for all values of the (anomalous) coupling constant.

7.Scalar propagator in a background gluon field beyond the eikonal approximation

Authors:Pedro Agostini

Abstract: In this study, we investigate the path integral representation of the scalar propagator in a background gluon field, extending beyond the eikonal approximation by considering all gauge field components and incorporating its $x^-$ dependence. Utilizing the worldline formalism, we integrate the Schwinger proper time to express the scalar propagator in light-cone coordinates, facilitating a direct comparison with known results in the literature. The derived propagator captures the longitudinal momentum exchange between the projectile and the medium. In the high-energy limit, our result simplifies to the effective gluon propagator employed in the BDMPS-Z formalism. Hence, we propose that our outcome serves as a foundational point for investigating corrections to the BDMPS-Z spectrum arising from the longitudinal momentum transfer of radiated gluons with the medium, as well as for studying collisional energy loss phenomena. Lastly, by employing an expansion around the classical saddle point solution, we systematically derive an eikonal expansion in inverse powers of the boost parameter, encompassing corrections related to longitudinal momentum transfer and interactions of the projectile with the transverse component of the field.

8.Order parameters for gauge invariant condensation far from equilibrium

Authors:Jürgen Berges, Kirill Boguslavski, Lillian de Bruin, Tara Butler, Jan M. Pawlowski

Abstract: Nuclear collisions at sufficiently high energies are expected to produce far-from-equilibrium matter with a high density of gluons at early times. We show gauge condensation, which occurs as a consequence of the large density of gluons. To identify this condensation phenomenon, we construct two local gauge-invariant observables that carry the macroscopic zero mode of the gauge condensate. The first order parameter for gauge condensation investigated here is the correlator of the spatial Polyakov loop. We also consider, for the first time, the correlator of the gauge invariant scalar field, associated to the exponent of the Polyakov loop. Using real-time lattice simulations of classical-statistical $SU(2)$ gauge theory, we find gauge condensation on a system-size dependent time scale $t_{\text{cond}} \sim L^{1/\zeta}$ with a universal scaling exponent $\zeta$. Furthermore, we suggest an effective theory formulation describing the dynamics using one of the order parameters identified. The formation of a condensate at early times may have intriguing implications for the early stages in heavy ion collisions.

1.Majorana Phase And Matter Effects In Neutrino Chiral Oscillation

Authors:Ming-Wei Li, Zhong-Lv Huang, Xiao-Gang He

Abstract: Due to finite masses and mixing, for neutrinos propagation in space-time, there is a chiral oscillation between left- and right- chiral neutrinos, besides the usual oscillation between different generations. The probability of chiral oscillation is suppressed by a factor of $m^2/E^2$ making the effect small for relativistic neutrinos. However, for non-relativistic neutrinos, this effects can be significant. In matter, the equation of motion is modified. When neutrinos produced in weak interaction pass through the matter, the effective energies are split into two different ones depending on the helicity of the neutrino. This results in different oscillation behavior for neutrinos with different helicity, in particular there is a new resonant effect related to the helicity state of neutrino different than the usual MSW effect. For Majorana neutrinos, chiral oscillation also depends on Majorana phases.

2.Thermal conductivity of evolving quark-gluon plasma in the presence of a time-varying magnetic field

Authors:Kamaljeet Singh, Jayanta Dey, Raghunath Sahoo

Abstract: The effect of the temperature evolution of QGP on its thermal conductivity and elliptic flow is investigated here in the presence of a time-varying magnetic field. Thermal conductivity plays a vital role in the cooling rate of the medium or its temperature evolution. The magnetic field produced during the early stages of (non-central) heavy-ion collisions decays with time, where electrical conductivity plays a significant role. As the medium expands, the electrical and thermal properties change, reflecting the effect in various observables. In this study, we have calculated the thermal conductivity of the QGP medium, incorporating the effects of temperature and magnetic field evolution. We discovered that conductivity significantly depends on the cooling rate and its value increases due to temperature evolution. Furthermore, the influence of these evolutions on the elliptic flow coefficient is measured, and elliptic flow is found to decrease.

3.The baryon number fluctuation $κσ^2$ as a probe of nuclear matter phase transition at high baryon density

Authors:Kun Xu, Mei Huang

Abstract: Two critical end points (CEPs) of the chiral phase transition and the nuclear liquid-gas phase transition show up at finite baryon chemical potential. The kurtosis $\kappa\sigma^2$ of baryon number fluctuation on the $T-\mu_B$ plane is positive on the first-order side and negative on the crossover side along the phase boundary. The freeze-out line extracted from the heavy ion collisions crosses between these two phase boundaries, one can observe a peak of $\kappa\sigma^2$ around the collision energy $5 {\rm GeV}$ near the CEP of the chiral phase transition, and negative $\kappa\sigma^2$ at low collision energies due to the CEP of the nuclear liquid-gas phase transition. This expalains the experimental measurement of $\kappa\sigma^2$ at the collision energies of 2.4 GeV at HADES and 3 GeV and 7.7-200 GeV at STAR for most central collision. Thus we propose that the baryon number fluctuation $\kappa\sigma^2$ can be used as a probe of nuclear matter phase structure at high baryon density.

4.Nuclear effects on tau lepton polarization in charged current deep inelastic $ν_τ/\barν_τ-A$ scattering

Authors:F. Zaidi, M. Sajjad Athar, S. K. Singh

Abstract: We have studied the tau-lepton polarization in the charged current $\nu_\tau/\bar\nu_\tau$ induced deep inelastic scattering (DIS) from the free nucleon as well as off the nuclear targets that are being used in ongoing and proposed experiments such as IceCube, DUNE, etc. For the free nucleon target, the differential scattering cross sections are obtained by taking into account the non-perturbative effect like target mass corrections (TMC) and the perturbative effect like the evolution of the parton densities at the next-to-leading order (NLO) in the four flavor $\overline{\textrm{MS}}-$scheme. In the case of nucleons bound inside a nuclear target, we have incorporated the nuclear medium effects such as Fermi motion, binding energy and nucleon correlations, through the use of nucleon spectral function. We shall present the results for the differential scattering cross sections and the longitudinal and transverse components of the tau-lepton polarization assuming time reversal invariance.

5.Soft-photon theorem for pion-proton elastic scattering revisited

Authors:Piotr Lebiedowicz, Otto Nachtmann, Antoni Szczurek

Abstract: We discuss the reactions $\pi p \to \pi p$ and $\pi p \to \pi p \gamma$ from a general quantum field theory (QFT) point of view. We consider the pion-proton elastic scattering both off shell and on shell. The on-shell amplitudes for $\pi^{\pm} p \to \pi^{\pm} p$ scattering are described by two invariant amplitudes, while the off-shell amplitudes contain eight invariant amplitudes. We study the photon emission amplitudes in the soft-photon limit where the photon energy $\omega \to 0$. The expansion of the $\pi^{\pm} p \to \pi^{\pm} p \gamma$ amplitudes to the orders $\omega^{-1}$ and $\omega^{0}$ is derived. These terms can be expressed by the on-shell invariant amplitudes and their partial derivatives with respect to $s$ and $t$. The term of order $\omega^{-1}$ is well known from the literature. Our term of order $\omega^{0}$ is new. The formulas given for the amplitudes in the limit $\omega \to 0$ are valid for both real and virtual photons. We also discuss the behavior of the corresponding cross-sections.

6.Weak production of $η$ mesons induced by $ν_μ(\barν_μ)$ at MicroBooNE energies

Authors:A. Fatima, M. Sajjad Athar, S. K. Singh

Abstract: We have studied neutral and charged current (anti)neutrino induced $\eta$ production off the free nucleon target at MicroBooNE energies, in the light of recent results reported by the MicroBooNE collaboration for the total $\eta$ production cross section. This study has been made using a theoretical model in which the weak hadronic current receives contribution from the nonresonant Born terms as well as from the resonance excitations. The Born terms are obtained using the SU(3) symmetric chiral model, used earlier in the study of $K-$meson production. The contribution from the resonance terms is considered from the excitation of five nucleon resonances viz. $S_{11}(1535)$, $S_{11}(1650)$, $P_{11}(1710)$, $P_{11}(1880)$, and $S_{11}(1895)$. To fix the parameters of the vector current interaction, this model is first used to study the electromagnetic production of $\eta$ mesons induced by real and virtual photons, and the theoretical results have been compared with the data from the MAINZ and JLab experiments. The partially conserved axial-vector current hypothesis and generalized Goldberger-Treiman relation are used to fix the parameters of the axial-vector current interaction. The results are presented for the total cross section for the neutral and charged current induced $\eta$ production, ratio of the cross sections for the charged current to neutral current, MicroBooNE flux averaged cross section $\langle \sigma \rangle$, $\left \langle \frac{d\sigma}{dQ^2} \right\rangle$ and $\left\langle \frac{d\sigma}{dp_\eta} \right\rangle$, which may be useful in the future analysis of MicroBooNE as well as other accelerator and atmospheric neutrino experiments being performed in the ${\cal O}$(1)~GeV energy region.

7.Diurnal modulation of electron recoils from DM-nucleon scattering through the Migdal effect

Authors:Mai Qiao, Chen Xia, Yu-Feng Zhou

Abstract: Halo dark matter (DM) particles could lose energy due to the scattering off nuclei within the Earth before reaching the underground detectors of DM direct detection experiments. This Earth shielding effect can result in diurnal modulation of the DM-induced recoil event rates observed underground due to the self-rotation of the Earth. For electron recoil signals from DM-electron scatterings, the current experimental constraints are very stringent such that the diurnal modulation cannot be observed for halo DM. We propose a novel type of diurnal modulation effect: diurnal modulation in electron recoil signals induced by DM-nucleon scattering via the Migdal effect. We set so far the most stringent constraints on DM-nucleon scattering cross section via the Migdal effect for sub-GeV DM using the S2-only data of PandaX-II and PandaX-4T with improved simulations of the Earth shielding effect. Based on the updated constraints, we show that the Migdal effect induced diurnal modulation of electron events can still be significant in the low energy region, and can be probed by experiments such as PandaX-4T in the near future.

8.Investigating the Single Production of Vector-Like Quarks Decaying into Top Quark and W Boson through Hadronic Channels at the HL-LHC

Authors:A. C. Canbay Ankara University, O. Cakir Ankara University

Abstract: We investigate the single production of vector-like quarks at the High Luminosity LHC (HL-LHC). With the assumed (enhanced) couplings to third generation quarks of the standard model, vector-like quarks $B/X$ are produced in association with a bottom ($b$) or top ($t$) quark, which correspond to $Bbq$ and $Btq/Xtq$ production modes, including an additional soft forward jet from the spectator quark ($q$). This study focuses on high-mass vector-like quarks $B/X$ decaying into a top quark and a $W$ boson, resulting in the final state jets emerging from hadronically decaying top quark ($t\to Wb$) and $W$ boson ($W\to q\bar{q}'$). The events with $W$ boson and $t$ quark have been analysed using tagging techniques for large-radius jets. The scan ranges of the mass ($1000<m_{B}<3000$ GeV) for the relative width $\Gamma_{B/X}/m_{B/X}=0.1$ of vector-like $B/X$ quarks have been investigated. From the results of the analysis, the masses of vector like quarks B (X) up to 2550 (2450) GeV can be excluded at $95\%$ CL depending on the type and branching scenarios at integrated luminosity projection of $3$ ab$^{-1}$ at the HL-LHC.

9.Probing mass orderings in presence of a very light sterile neutrino in a liquid argon detector

Authors:Animesh Chatterjee, Srubabati Goswami, Supriya Pan

Abstract: Results from experiments like LSND and MiniBooNE hint towards the possible presence of an extra eV scale sterile neutrino. The addition of such a neutrino will significantly impact the standard three flavour neutrino oscillations. In particular, it can give rise to additional degeneracies due to additional sterile parameters. For an eV scale sterile neutrino, the cosmological constraints dictate that the sterile state is heavier than the three active states. However, for lower masses of sterile neutrinos, it can be lighter than one and/or more of the three states. In such cases, the mass ordering of the sterile neutrinos also becomes unknown along with the mass ordering of the active states. In this paper, we explore the mass ordering sensitivity in the presence of a sterile neutrino assuming the mass squared difference $|\Delta_{41}|$ to be in the range $10^{-4} - 1$ eV$^2$. We study (i) how the ordering of the active states, i.e. the determination of the sign of $\Delta_{31}$ gets affected by the presence of a sterile neutrino in the above mass range, (ii) the possible determination of the sign of $\Delta_{41}$ for $\Delta_{41}$ in the range $10^{-4} - 0.1$ eV$^2$. This analysis is done in the context of a liquid argon detector using both beam neutrinos traveling a distance of 1300 km and atmospheric neutrinos which propagates through a distance ranging from 10 - 10000 km allowing resonant matter effects. Apart from presenting separate results from these sources, we also do a combined study and probe the synergy between these two in giving an enhanced sensitivity.

10.On the impact of the Migdal effect in reactor CE$ν$NS experiments

Authors:M. Atzori Corona, M. Cadeddu, N. Cargioli, F. Dordei, C. Giunti

Abstract: The search for coherent elastic neutrino nucleus scattering (CE$\nu$NS) using reactor antineutrinos represents a formidable experimental challenge, recently boosted by the observation of such a process at the Dresden-II reactor site using a germanium detector. This observation relies on an unexpected enhancement at low energies of the measured quenching factor with respect to the theoretical Lindhard model prediction, which implies an extra observable ionization signal produced after the nuclear recoil. A possible explanation for this additional contribution could be provided by the so-called Migdal effect, which however has never been observed. Here, we study in detail the impact of the Migdal contribution to the standard CE$\nu$NS signal calculated with the Lindhard quenching factor, finding that the former is completely negligible for observed energies below $\sim 0.3\,\mathrm{keV}$ where the signal is detectable, and thus unable to provide any contribution to CE$\nu$NS searches in this energy regime. To this purpose, we compare different formalisms used to describe the Migdal effect that intriguingly show a perfect agreement, making our findings robust.

1.Complementarity of $μ$TRISTAN and Belle II in searches for charged-lepton flavour violation

Authors:Gabriela Lichtenstein, Michael A. Schmidt, German Valencia, Raymond R. Volkas

Abstract: We analyse the potential of the proposed $\mu^+ \mu^+$ and $\mu^+ e^-$ collider $\mu$TRISTAN to complement the searches for charged-lepton flavour-violation (CLFV) that can be carried out by Belle II. $\mu$TRISTAN offers the possibility of directly producing and studying new resonances that could mediate CLFV for a certain range of masses. In addition, we find that it can produce competitive bounds to those from Belle II for cases where the new resonance lies beyond direct reach. We illustrate these points with three $Z_3$ "lepton triality" models, where we also find an example that can only be probed by $\mu$TRISTAN. These three models feature doubly-charged scalars, denoted $k_{1,2,3}$ respectively, that induce both CLFV and flavour-conserving processes. Tree-level $k_1$ exchange induces the CLFV scattering process $\mu^+ e^- \to e^+ \tau^-$, while $k_2$ interactions induce $\mu^+ \mu^+ \to \tau^+ e^+$, $\mu^+ e^- \to \tau^+ \mu^-$ and make a non-SM contribution to the flavour-conserving scattering $\mu^+ \mu^+ \to \mu^+ \mu^+$. The $k_3$ model has a non-SM contribution to the flavour-conserving process $\mu^+ e^- \to \mu^+ e^-$. Other scattering processes involving $k_1$, $k_2$ or $k_3$ are not relevant for $\mu$TRISTAN and outside the scope of our analysis. We quantify the sensitivity of $\mu$TRISTAN for each of these processes. For the $k_1$ and $k_2$ cases we compare the $\mu$TRISTAN reach to the expected sensitivity of Belle II to the crossing symmetry related CLFV $\tau$ decays.

2.Stability of neutrino oscillation parameters at low energy scale with the variations of SUSY breaking scale under Renormalisation Group Equations

Authors:Kh. Helensana Devi, K. Sashikanta Sngh, N. Nimai Singh

Abstract: We discuss the stability of the neutrino oscillation parameters at low energy scale including self-complementarity (SC) relations among mixing angles under radiative corrections with the variation of SUSY breaking scale ($m_s$) in both normal and inverted hierarchical cases. We observe that the neutrino oscillation parameters including the SC relation maintains stability at the electroweak scale within $1\sigma$ range of the latest global fit data. NH case maintains more stability than IH case. All the numerical values related to the absolute neutrino masses viz., $\Sigma |m_i|$, $m_{\beta}$ and $m_{ \beta \beta}$ are found to lie below the observational upper bound.

3.The role of the pion in the lineshape of the $X(3872)$

Authors:Angelo Esposito, Davide Germani, Alfredo Glioti, Antonio D. Polosa, Riccardo Rattazzi, Michele Tarquini

Abstract: We determine the contribution of long-range pion interactions to the $X(3872)$ dynamics, assuming it is a loosely bound $D^0 \bar{D}^{*0}$ molecule. Our result is based on the distorted wave Born approximation in non-relativistic quantum mechanics. Despite their long-range nature, we find that pion interactions cannot produce a large and negative effective range. Nonetheless, they introduce imaginary parts. In particular, they contribute to the total decay width of the $X(3872)$ with a term associated with, but not precisely corresponding to, the $D^*$ width. Our approach can also be applied to the recently discovered $T_{cc}^+$ states.

4.Quarkonium spectroscopy of the linear plus modified Yukawa potential

Authors:Kaushal R Purohit, Pooja Jakhad, Ajay Kumar Rai

Abstract: In this article, the linear plus modified Yukawa potential (LIMYP) is used as the quark antiquark interaction potential for the approximate analytical bound state solution of the Klein Gordon equation in three-dimensional space. The energy eigenvalues and associated wavefunction are obtained by solving the Klein Gordon equation analytically using the Nikiforov Uvarov (NU) method. The mass spectra of heavy mesons such as charmonium $(c\bar{c})$, bottomonium $(b\bar{b})$, and $b\bar{c}$ for various quantum states are obtained using the energy spectra expression. In comparison to experimental data, graphical modification of acquired mass spectra of heavy mesons with the parameter employed in the energy equation and the current potential provides good results.

5.Nano-Hertz gravitational waves from collapsing domain walls associated with freeze-in dark matter in light of pulsar timing array observations

Authors:Zhao Zhang, Chengfeng Cai, Yu-Hang Su, Shiyu Wang, Zhao-Huan Yu, Hong-Hao Zhang

Abstract: Evidence for a stochastic gravitational wave background in the nHz frequency band is recently reported by four pulsar timing array collaborations NANOGrav, EPTA, CPTA, and PPTA. It can be interpreted by gravitational waves from collapsing domain walls in the early universe. We assume such domain walls arising from the spontaneous breaking of a $Z_2$ symmetry in a scalar field theory, where a tiny $Z_2$-violating potential is required to make domain walls unstable. We propose that this $Z_2$-violating potential is radiatively induced by a feeble Yukawa coupling between the scalar field and a fermion field, which is also responsible for dark matter production via the freeze-in mechanism. Combining the pulsar timing array data and the observed dark matter relic density, we find that the model parameters can be narrowed down to small ranges.

6.Exploring slicing variables for jet processes

Authors:Luca Buonocore, Massimiliano Grazzini, Jürg Haag, Luca Rottoli, Chiara Savoini

Abstract: We consider the class of inclusive hadron collider processes in which one or more energetic jets are produced, possibly accompanied by colourless particles. We provide a general formulation of a slicing scheme for this class of processes, by identifying the various contributions that need to be computed up to next-to-leading order (NLO) in QCD perturbation theory. We focus on two novel observables, the one-jet resolution variable $\Delta E_t$ and the $n$-jet resolution variable $k_{T}^{\mathrm{ness}}$, and explicitly compute all the ingredients needed to carry out NLO computations using these variables. We contrast the behaviour of these variables when the slicing parameter becomes small. In the case of $k_{T}^{\mathrm{ness}}$ we also present results for the hadroproduction of multiple jets.

7.Exploring Solar Neutrino Oscillation Parameters with LCS at Yemilab and JUNO

Authors:Pouya Bakhti, Meshkat Rajaee, Seon-Hee Seo, Seodong Shin

Abstract: We investigate the sensitivities of the liquid scintillator counter (LSC) at Yemilab and JUNO to solar neutrino oscillation parameters, focusing on $\theta_{12}$ and $\Delta m^2_{21}$. We compare the potential of JUNO with LSC at Yemilab utilizing both reactor and solar data in determining those parameters. We find that the solar neutrino data of LSC at Yemilab is highly sensitive to $\theta_{12}$ enabling its determination with exceptional precision. Our study also reveals that if $\Delta m^2_{21}$ is larger, with a value close to the best fit value of KamLAND, JUNO reactor data will have about two times better precision than the reactor LSC at Yemilab. On the other hand, if $\Delta m^2_{21}$ is smaller and closer to the best fit value of solar neutrino experiments, the precision of the reactor LSC at Yemilab will be comparable/better than JUNO.

8.Two-pole structures demystified: chiral dynamics at work

Authors:Jia-Ming Xie, Jun-Xu Lu, Li-Sheng Geng, Bing-Song Zou

Abstract: In the past two decades, one of the most puzzling phenomena discovered in hadron physics is that a nominal hadronic state can actually correspond to two poles on the complex energy plane. This phenomenon was first noticed for the $\Lambda(1405)$, and then for $K_1(1270)$ and to a less extent for $D_0^*(2300)$. In this Letter, we show explicitly how the two-pole structures emerge from the underlying chiral dynamics describing the coupled-channel interactions between heavy matter particles and Nambu-Goldstone bosons. In particular, the fact that two poles appear between the two dominant coupled channels can be attributed to the particular form of the leading order chiral potentials of the Weinberg-Tomozawa form. Their lineshapes overlap with each other because the degeneracy of the two coupled channels is only broken by explicit chiral symmetry breaking of higher order. We predict that for light-quark~(pion) masses heavier than their physical values, the two-pole structures disappear, which can be easily verified by future lattice QCD simulations. Furthermore, we anticipate similar two-pole structures in other systems, such as the isopin $1/2$ $\bar{K}\Sigma_c-\pi\Xi'_c$ coupled channel, which await for experimental discoveries.

9.Primordial black holes as dark matter: Interferometric tests of phase transition origin

Authors:Iason Baldes, María Olalla Olea-Romacho

Abstract: We show that primordial black holes - in the observationally allowed mass window with $f_{\rm pbh}=1$ - formed from late nucleating patches in a first order phase transition imply upcoming gravitational wave interferometers will see a large stochastic background arising from the bubble collisions. As an example, we use a classically scale invariant $B-L$ model, in which the right handed neutrinos explain the neutrino masses and leptogenesis, and the dark matter consists of primordial black holes. The conclusion regarding the gravitational waves is, however, expected to hold model independently for black holes coming from such late nucleating patches.

10.Signatures of vacuum birefringence in low-power flying focus pulses

Authors:Martin Formanek, John P. Palastro, Dillon Ramsey, Stefan Weber, Antonino Di Piazza

Abstract: Vacuum birefringence produces a differential phase between orthogonally polarized components of a weak electromagnetic probe in the presence of a strong electromagnetic field. Despite representing a hallmark prediction of quantum electrodynamics, vacuum birefringence remains untested in pure light configurations due to the extremely large electromagnetic fields required for a detectable phase difference. Here, we exploit the programmable focal velocity and extended focal range of a flying focus laser pulse to substantially lower the laser power required for detection of vacuum birefringence. In the proposed scheme, a linearly polarized x-ray probe pulse counter-propagates with respect to a flying focus pulse, whose focus moves at the speed of light in the same direction as the x-ray probe. The peak intensity of the flying focus pulse overlaps the probe over millimeter-scale distances and induces a polarization ellipticity on the order of $10^{-10}$, which lies within the detection sensitivity of existing x-ray polarimeters.

11.Electric Dipole Moments as Probes of $B$ Anomaly

Authors:Syuhei Iguro, Teppei Kitahara

Abstract: The measurements of the lepton flavor universality (LFU) in $\mathcal{B}({\,\overline{\!B}} \to D^{(\ast)} l \overline{\nu})$ indicate a significant deviation from the standard model prediction at a 3-4 $\sigma$ level, revealing a violation of the LFU ($R_{D^{(\ast)}}$ anomaly). It is known that the $R_{D^{(\ast)}}$ anomaly can be easily accommodated by an $SU(2)_L$-singlet vector leptoquark (LQ) coupled primarily to third-generation fermions, whose existence is further motivated by a partial gauge unification. In general, such a LQ naturally leads to additional $CP$-violating phases in the LQ interactions. In this Letter, we point out that the current $R_{D^{(\ast)}}$ anomaly prefers the $CP$-violating interaction although $\mathcal{B}({\,\overline{\!B}} \to D^{(\ast)} l\overline{\nu})$ is a $CP$-conserving observable. The $CP$-violating LQ predicts a substantial size of the bottom-quark electric dipole moment (EDM), the chromo-EDM, and also the tau-lepton EDM. Eventually, at low energy, the nucleon and electron EDMs are induced. Therefore, we conclude that the $R_{D^{(\ast)}}$ anomaly with the $SU(2)_L$-singlet vector LQ provides unique predictions: neutron and proton EDMs with opposite signs and a magnitude of $\mathcal{O}(10^{-27})\,e\,$cm, with a null electron EDM signal. These EDMs could serve as crucial indicators in future experiments.

1.C/CP symmetry violation of $n-n^{\prime}$ and $\overline{n}-\overline{n}^{\prime}$ transitions in a two-brane universe: a baryogenesis portal

Authors:Michael Sarrazin

Abstract: For the past decade, there has been significant interest in the experimental search for neutron-hidden neutron $n-n^{\prime}$ transitions as predicted by various theoretical models, such as braneworld scenarios where the dark sector resides on a hidden brane. In a recent study, it was demonstrated that a C/CP asymmetry between $n-n^{\prime}$ and $\overline{n}-\overline{n}^{\prime}$ transitions can explain baryogenesis. However, the origins of this asymmetry and its required magnitude were only suggested. In this paper, we demonstrate that both aspects naturally occur due to the presence of an extra scalar field supported by the $U(1)\times U(1)$ gauge group, which extends the conventional electromagnetic gauge field in the two-brane universe.

2.Spectroscopy of Heavy-Light Mesons ($c\bar{s}$, $c\bar{q}$, $b\bar{s}$, $b\bar{q}$) for the linear plus modified Yukawa potential using Nikiforov-Uvarov Method

Authors:Kaushal R Purohit, Ajay Kumar Rai, Rajendrasinh H Parmar

Abstract: An approximate bound state solution of the Klein-Gordon equation is derive analytically for the 3-dimensional space with a combination framework of linear plus modified Yukawa Potential (LIMYP) using the Nikiforov-Uvarov (N-U) method for obtaining the energy eigenvalues and corresponding wave function. A detailed study of mass spectra of all combination sets of heavy-light flavor mesons vis-a-vis $(Ks/Kq; K= C, B)$ is investigated by treating both heavy-light flavor mesons non-relativistic with an effective quark-antiquark interaction potential for different quantum states. Along with that, an elucidated graphical representation is scrutinized with the calculated mass spectra obtained from the energy eigenvalue against the corresponding variables for all the combination sets of heavy-light flavors mesons. Therefore, the current framework potential provides excellent reconciliation with the experimental data of states known to date and minuscule \% difference in lower quantum states, which increases with higher quantum states that can be correlated with the higher screening factor coming into the account.

3.A model for pion collinear parton distribution function and form factor

Authors:Simone Venturini, Barbara Pasquini, Simone Rodini

Abstract: We developed a model for the pion light-front wave function (LFWF) that incorporates valence, sea and gluon degrees of freedom. Using the LFWF overlap representation, we derived parametrizations for the pion parton distribution functions and the electromagnetic form factor. These parametrizations depend on two distinct sets of parameters, enabling separate fits of the longitudinal- and transverse-momentum dependencies of the LFWF. The pion PDFs are extracted from available Drell-Yan and photon-production data using the xFitter framework and are found well compatible with existing extractions. Furthermore, the fit of the electromagnetic form factor of the pion to all the available experimental data works quite successfully.

4.Probing the weak mixing angle at high energy

Authors:Clara Lavinia Del Pio, Simone Amoroso, Mauro Chiesa, Ekaterina Lipka, Fulvio Piccinini, Federico Vazzoler, Alessandro Vicini

Abstract: The weak mixing angle is a probe of the vector-axial coupling structure of electroweak interactions. It has been measured precisely at the $Z$-pole by experiments at the LEP and SLD colliders, but its energy dependence above $M_Z$ remains unconstrained. In this contribution we propose to exploit measurements of Neutral-Current Drell Yan at large invariant dilepton masses at the Large Hadron Collider, to determine the scale dependence of the weak mixing angle in the $\overline{MS}$ renormalisation scheme, $\sin^2 \theta_w^{\overline{MS}}(\mu)$. Such a measurement can be used to test the Standard Model predictions for the $\overline{MS}$ running at TeV scales, and to set model-independent constraints on new states with electroweak quantum numbers. To this end, we present an implementation of $\sin^2 \theta_w^{\overline{MS}}(\mu)$ in the POWHEG-BOX Monte Carlo event generator, which we use to explore the potential of future analyses with the LHC Run~3 and High-Luminosity datasets. In particular, the impact of the higher order corrections and of the uncertainties due to the knowledge of parton distribution functions are studied.

5.Mass and decay of the $s\bar{s}$ member of the $1^{3}F_{4}$ meson nonet

Authors:Xue-Chao Feng, Ke-Wei Wei

Abstract: The mass and decay of the $s\bar{s}$ member of the $1^{3}F_{4}$ meson nonet are investigated in the framework of the Regge phenomenology and the $^{3}P_{0}$ model. We propose, based on the results, that the assignment of the $s\bar{s}$ member of the $1^{3}F_{4}$ meson nonet will require additional testing in the future. Our results also provide information for future studies of the $1^{3}F_{4}$ meson nonet.

6.Fluid dynamics from the Boltzmann equation using a maximum entropy distribution

Authors:Chandrodoy Chattopadhyay, Ulrich Heinz, Thomas Schaefer

Abstract: Using the recently developed ``Maximum Entropy'' (or ``least biased'') distribution function to truncate the moment hierarchy arising from kinetic theory, we formulate a far-from-equilibrium macroscopic theory that provides the possibility of describing both free-streaming and hydrodynamic regimes of heavy-ion collisions within a single framework. Unlike traditional hydrodynamic theories that include viscous corrections to finite order, the present formulation incorporates contributions to all orders in shear and bulk inverse Reynolds numbers, allowing it to handle large dissipative fluxes. By considering flow profiles relevant for heavy-ion collisions (Bjorken and Gubser flows), we demonstrate that the present approach provides excellent agreement with underlying kinetic theory throughout the fluid's evolution and, especially, in far-off-equilibrium regimes where traditional hydrodynamics breaks down.

7.Lepton flavor violating dark photon

Authors:Alexey S. Zhevlakov, Dmitry V. Kirpichnikov, Valery E. Lyubovitskij

Abstract: We study possible impact of dark photons on lepton flavor phenomenology. We derive the constraints on non-diagonal dark photon couplings with leptons by analyzing corresponding contributions to lepton anomalous magnetic moments, rare lepton decays and the prospects of fixed-target experiments aiming for search for light dark matter based on missing energy/momentum techniques.

8.Correlating neutrino magnetic moment and scalar triplet dark matter to enlighten XENONnT bounds in a Type-II model

Authors:Shivaramakrishna Singirala, Dinesh Kumar Singha, Rukmani Mohanta

Abstract: We investigate neutrino magnetic moment, triplet scalar dark matter in a Type-II radiative seesaw scenario. With three vector-like fermion doublets and two scalar triplets, we provide a loop level setup for the electromagnetic vertex of neutrinos. All the scalar multiplet components constitute the total dark matter abundance of the Universe and also their scattering cross section with detector lie below the experimental upper limit. Using the consistent parameter space in dark matter domain, we obtain light neutrino mass in sub-eV scale and also magnetic moment in the desired range. We further derive the constraints on neutrino transition magnetic moments, consistent with XENONnT limit.

9.Radiative decays of the heavy-quark-spin molecular partner of $T_{cc}^+$

Authors:Zhao-Sai Jia, Zhen-Hua Zhang, Gang Li, Feng-Kun Guo

Abstract: With the assumptions that the $T_{cc}^+$ discovered at LHCb is a $D^{*}D$ hadronic molecule, using a nonrelativistic effective field theory we calculate the radiative partial widths of $T_{cc}^* \to D^*D\gamma$ with $T_{cc}^*$ being a $D^{*}D^{*}$ shallow bound state and the heavy-quark-spin partner of $T_{cc}^+$. The $I=0$ $D^*D$ rescattering effect with the $T_{cc}$ pole is taken into account. The results show that the isoscalar $D^{\ast} D$ rescattering can increase the tree-level decay width of $T_{cc}^{\ast +}\rightarrow D^{*+}D^0\gamma$ by about $50\%$, while decrease that of $T_{cc}^{\ast +}\rightarrow D^{*0}D^+\gamma$ by a similar amount. The two-body partial decay widths of the $T_{cc}^{*+}$ into $T_{cc}^+\gamma$ and $T_{cc}^+\pi^0$ are also calculated, and the results are about $6~\rm{keV}$ and $3~\rm{keV}$, respectively. Considering that the $D^*$ needs to be reconstructed from the $D\pi$ or $D\gamma$ final state in an experimental measurement, the four-body partial widths of the $T_{cc}^{*+}$ into $DD\gamma\gamma$ and $DD\pi\gamma$ are explicitly calculated, and we find that the interference effect between different intermediate $D^*D\gamma$ states is small. The total radiative decay width of the $T_{cc}^*$ is predicted to be about $24~\rm{keV}$. Adding the hadronic decay widths of $T_{cc}^* \to D^*D\pi$, the total width of the $T_{cc}^*$ is finally predicted to be $(65\pm2)$ keV.

10.Astrophysical Constraints on Decaying Dark Gravitons

Authors:Jamie A. P. Law-Smith, Georges Obied, Anirudh Prabhu, Cumrun Vafa

Abstract: In the dark dimension scenario, which predicts an extra dimension of micron scale, dark gravitons (KK modes) are a natural dark matter candidate. In this paper, we study observable features of this model. In particular, their decay to standard matter fields can distort the CMB and impact other astrophysical signals. Using this we place bounds on the parameters of this model. In particular we find that the natural range of parameters in this scenario is consistent with these constraints and leads to the prediction that the mean mass of the dark matter today is less than a few hundred keV and the size of the extra dimension is greater than $\sim 10 \;\mu\mathrm{m}$.

11.Comprehensive Measurement Forecasts of the EeV Neutrino-Nucleon Cross Section with Cosmic Neutrinos at IceCube-Gen2

Authors:Victor B. Valera, Mauricio Bustamante, Christian Glaser

Abstract: The investigation of neutrino interactions with matter serves as a valuable tool for understanding the fundamental structure of nucleons and potentially uncovering novel physics phenomena. To date, the neutrino-nucleon cross section has been examined across a range of energies spanning from a few hundred MeV to PeV. However, the pursuit of ultra-high-energy (UHE) cosmic neutrinos, surpassing 100 PeV in energy, holds the promise of further advancements. In the next 10-20 years, UHE neutrino telescopes, currently in the planning stage, may ultimately succeed in their detection. This article presents pioneering and comprehensive estimation forecasts for the ultra-high-energy neutrino-nucleon cross section, with a specific focus on the employment of neutrino radio-detection within the IceCube-Gen2 experiment. The study incorporates cutting-edge methodologies in UHE neutrino flux prediction, neutrino propagation within the Earth, radio detection techniques, and the treatment of background data to facilitate accurate cross section measurement projections. Assuming the successful detection of at least a few tens of UHE neutrino-induced events over a 10-year period, IceCube-Gen2 could achieve, for the first time, the measurement of the cross section at center-of-mass energies of approximately $\sqrt{s} \approx 10$--100 TeV. Furthermore, if the number of events exceeds one hundred, the precision of the cross section measurement could be comparable to its corresponding theoretical prediction.

12.On the sensitivity reach of LQ production with preferential couplings to third generation fermions at the LHC

Authors:A. Flórez, J. Jones-Pérez, A. Gurrola, C. Rodriguez, J. Peñuela-Parra

Abstract: Leptoquarks (LQs) are hypothetical particles that appear in various extensions of the Standard Model (SM) that can explain observed differences between SM theory predictions and experimental results. The production of these particles has been widely studied at various experiments, most recently at the Large Hadron Collider (LHC), and stringent bounds have been placed on their masses and couplings, assuming the simplest beyond-SM (BSM) hypotheses. However, the limits are significantly weaker for LQ models with family non-universal couplings containing enhanced couplings to third-generation fermions. We present a new study on the production of a LQ at the LHC, with preferential couplings to third-generation fermions, considering proton-proton collisions at $\sqrt{s} = 13$ $\mathrm{TeV}$ and $\sqrt{s} = 13.6$ $\mathrm{TeV}$. Such a hypothesis is well motivated theoretically and it can explain the recent anomalies in the precision measurements of $\mathrm{B}$-meson decay rates, specifically the $R_{D^{(*)}}$ ratios. Under a simplified model where the LQ masses and couplings are free parameters, we focus on cases where the LQ decays to a $\tau$ lepton and a $\mathrm{b}$ quark, and study how the results are affected by different assumptions about chiral currents and interference effects with other BSM processes with the same final states, such as diagrams with a heavy vector boson, $\mathrm{Z}^{'}$. The analysis is performed using machine learning techniques, resulting in an increased discovery reach at the LHC and allowing us to probe the entirety of the new physics phase space which addresses the $\mathrm{B}$-meson anomalies, for LQ masses up to 2.25 $\mathrm{TeV}$.

13.Glauber Phases in Non-Global LHC Observables: Resummation for Quark-Initiated Processes

Authors:Philipp Böer JGU Mainz, Matthias Neubert JGU Mainz, Michel Stillger JGU Mainz

Abstract: It has been known for many years that jet cross sections at hadron colliders exhibit double-logarithmic corrections starting at four-loop order, arising from two soft Glauber-gluon interactions between the two colliding partons. The resummation of these "super-leading logarithms" has been achieved only recently by means of a renormalization-group treatment in soft-collinear effective theory. We generalize this result and, within the same framework and for quark-initiated processes, resum the double logarithms arising in the presence of an arbitrary number of Glauber-gluon exchanges. For typical choices of parameters, the higher-order Glauber terms give rise to corrections which are expected to be numerically of the same magnitude as the super-leading logarithms. However, we find that the Glauber series for jet cross sections is dominated by the two-Glauber contribution.

1.Spatial imaging of proton via leading-twist GPDs with basis light-front quantization

Authors:Satvir Kaur, Siqi Xu, Chandan Mondal, Xingbo Zhao, James P. Vary

Abstract: The internal image of the proton is unveiled by examining the three-dimensional distribution functions, the generalized parton distributions (GPDs), within the basis light-front quantized environment. Several distributions emerge when a quark is sampled with different currents depending upon the helicity arrangements of the active quark and the proton target. We investigate all the leading-twist proton GPDs of the valence quarks, the helicity conserving distributions $(H,\, E,\, \tilde{H}, \,\tilde{E})$ as well as the helicity non-conserving $(H_T,\,E_T,\,\tilde{H}_T,\,\tilde{E}_T)$ distributions. We present the Mellin moments of these distribution functions, where the first moment produces a form factor and the second Mellin moments help extract the information on partonic contributions to the hadronic angular momentum. We compare our results for the Mellin moments with those from lattice QCD and other approaches where available. We also present the GPDs in transverse position space.

2.Inverse problem in femtoscopic correlation functions: The $T_{cc}(3875)^+$ state

Authors:M. Albaladejo, A. Feijoo, I. Vidaña, J. Nieves, E. Oset

Abstract: We study here the inverse problem of starting from the femtoscopic correlation functions of related channels and analyze them with an efficient tool to extract the maximum information possible on the interaction of the components of these channels, and the existence of possible bound states tied to this interaction. The method is flexible enough to accommodate non-molecular components and the effect of missing channels relevant for the interaction. We apply the method to realistic correlation functions for the $D^{*+}D^0$ and $D^{*0}D^+$ channels derived consistently from the properties of the $T_{cc}(3875)^+$ and find that we can extract the existence of a bound state, its nature as a molecular state of the $D^{*+}D^0$ and $D^{*0}D^+$ channels, the probabilities of each channel, as well as scattering lengths and effective ranges for the channels, together with the size of the source function, all of them with a relatively good precision.

3.Predictions of the ratio and asymmetry probes of the invisible $Z$-boson decay

Authors:Kadir Saygin

Abstract: Higher-order predictions through the combined accuracy including next-to-leading order (NLO) electroweak (EW) and next-to-NLO (NNLO) quantum chromodynamics (QCD) corrections in underlying perturbation theories are presented thoroughly for the invisible decay of the $Z$ boson into neutrino pair relative to its decay into charged-lepton pair (leptonic decay). The combined NNLO QCD+NLO EW predictions are achieved based on the fully-differential calculations of cross sections of both the invisible and leptonic processes in proton-proton ($pp$) collisions at 13 TeV center-of-mass energy. Differential distributions of cross-section ratios of the invisible process to the leptonic process are presented as a function of the transverse momentum of the $Z$ boson $p^{Z}_{\rm{T}}$. For the first time, the predictions for differential distributions of cross-section asymmetries between the invisible process and the leptonic process are presented in bins of the $p^{Z}_{\rm{T}}$. The cross-section ratio and asymmetry distributions, which are referred to as the invisible probes, are considered to be important for controlling the invisible process by the leptonic process of the $Z$ boson and probing deviation from the Standard Model (SM) for new-physics searches. The predictions are extensively presented beyond the $Z$-boson mass resonance region to assess the potential of the invisible ratio and asymmetry probes for new-phenomena searches in high-invariant mass region of the lepton-pair final states. Various tests with threshold requirements of transverse momenta of neutrino pair and leptons are performed to assess the impact on the combined predictions. The invisible ratio and asymmetry probes are proposed to be important probes for indirect searches of new-physics scenarios.

4.Miniclusters from axion string simulations

Authors:Giovanni Pierobon, Javier Redondo, Ken'ichi Saikawa, Alejandro Vaquero, Guy D. Moore

Abstract: The properties of axion miniclusters and of the voids between them can have very strong implications for the discovery of axions and the dark matter of the Universe. These properties can be strongly affected by axion dynamics in the early Universe, such as the axion string network and the non-linear dynamics around the QCD phase transition. Recently, improvements in numerical simulation techniques have allowed us to calculate the dark matter axion field from axion strings and QCD effects using different methods: directly with low-tension strings but high resolution, directly with effective high-tension strings, or indirectly by extrapolating an attractor solution. In this work, we study the properties of miniclusters in the different approaches used in the literature. We find that, while there are substantial differences in the mass distribution and internal density profiles, globally there is a similar energy distribution between minicluster halos and voids.

5.FCNCs, Proton Stability, $ g_μ-2$ Discrepancy, Neutralino cold Dark Matter in Flipped $SU(5) \times U(1)_χ$ from $F$ Theory based on $ A_{4} $ Symmetry

Authors:Gayatri Ghosh

Abstract: We predict the low energy signatures of a Flipped $SU(5) \times U(1)_{\chi}$ effective local model , constructed within the framework of F$-$theory based on $ A_{4} $ symmetry. The Flipped SU(5) model from F Theory in the field of particle physics is prominent due to its ability to construct realistic four-dimensional theories from higher-dimensional compactifications necessitates a uni ed description of the fundamental forces and particles of nature used for exploring various extensions of the Standard Model. We study Flipped $SU(5) \times U(1)_{\chi}$ Grand Unified Theories (GUTs) with $ A_{4} $ modular symmetry. In our model with different modular weights assignments, the fermion mass hierarchy exists due to different weighton fields. The constraints on the Dirac neutrino Yukawa matrix allows a good tuning to quark and charged lepton masses and mixings for each weighton field, with the neutrino masses and lepton mixing well determined by the type I seesaw mechanism, at the expense of some tuning which will be observed in charged lepton flavour violating decays which we explore here. The minimal ipped $SU(5$) model is supplemented with an extra right-handed type and its complex conjugate electron state, $ E_{c} + \bar{E_{c}} $, as well as neutral singlet fields. The $ E_{c} + \bar{E_{c}} $ pair gets masses of the order of TeV which solves the $ g_{\mu}- 2$ discrepancy. The predictions of the model for charged lepton avour violation decay rate and proton decay could be tested in near future experiments.

6.Quantum simulation of jet evolution in a medium

Authors:Wenyang Qian

Abstract: Jets provide one of the primary probes of the quark-gluon plasma produced in ultrarelativistic heavy ion collisions and the cold nuclear matter explored in deep inelastic scattering experiments. However, despite important developments in the last years, a description of the real-time evolution of QCD jets inside a medium is still far from complete. In our previous work, we have explored quantum technologies as a promising alternative theoretical laboratory to simulate jet evolution in QCD matter, to overcome inherent technical difficulties in present calculations. Here, we extend our previous investigation from the single particle to the multiple particle Fock spaces, taking into account gluon production. Based on the light-front Hamiltonian formalism, we construct a digital quantum circuit that tracks the evolution of a multi-particle jet probe in the presence of a stochastic color background. Using the quantum simulation algorithm, we show the medium-induced modification to the jet evolution in both the momentum broadening and gluon production.

7.Taming a leading theoretical uncertainty in HH measurements via accurate simulations for bbH production

Authors:Stefano Manzoni, Elena Mazzeo, Javier Mazzitelli, Marius Wiesemann, Marco Zaro

Abstract: We present a new simulation for Higgs boson production in association with bottom quarks ($b\bar{b}H$) at next-to-leading order (NLO) accuracy matched to parton showers in hadronic collisions. Both contributions, the standard one proportional to the bottom-quark Yukawa coupling and the loop-induced one proportional to the top-quark Yukawa coupling from the gluon-fusion process, are taken into account in a scheme with massive bottom quarks. Therefore, we provide the full simulation of the $b\bar{b}H$ final state in the Standard Model, which constitutes also a crucial background to measurements for Higgs-boson pair ($HH$) production at the Large Hadron Collider when at least one of the Higgs bosons decays to bottom quarks. So far, the modeling of the $b\bar{b}H$ final state induced one of the dominant theoretical uncertainties to $HH$ measurements, as the gluon-fusion component was described only at the leading order (LO) with uncertainties of $\mathcal{O}(100\%)$. Including NLO corrections in its simulation allows us to reduce the scale dependence to $\mathcal{O}(50\%)$ so that it becomes subdominant with respect to other systematic uncertainties. As a case study, we provide an in-depth analysis of the $b\bar{b}H$ background to $HH$ measurements with realistic selection cuts in the $2b2\gamma$ channel. We also compare our novel simulation with the currently-employed ones, discussing possible issues and shortcomings of a scheme with massless bottom quarks. Finally, we propagate the effect of the new $b\bar{b}H$ simulation to $HH$ searches in the $2b2\gamma$ and $2b2\tau$ final states, and we find an improvement of up to 10% (20%) on the current (HL-LHC) limits on the $HH$ cross section.

8.Split NMSSM from dimensional reduction of a $10D$, $\mathcal{N}=1$ $E_8$ over $SU(3)/U(1)\times U(1)\times Z_3$

Authors:Gregory Patellis, Werner Porod, George Zoupanos

Abstract: We examine an extension of the Standard Model which results from a $10D$, $\mathcal{N}=1$, $E_8$ gauge theory. The theory is dimensionally reduced over a $M_4 \times B_0/ \mathbf{Z}_3 $ space, where $B_0$ is the nearly-K\"ahler manifold $SU(3)/U(1) \times U(1)$ and $\mathbf{Z}_3$ is a freely acting discrete group on $B_0$ that triggers a Wilson flux breaking, leading to an $\mathcal{N}=1$, $SU(3)^3\times U(1)^2$ effective theory in $4D$. At lower energies we are left with the Split NMSSM. Its 2-loop analysis yields third generation quark and light Higgs masses within the experimental limits and predicts a neutralino LSP mass $<800$ GeV.

9.Accidentally light scalars from large representations

Authors:Felix Brümmer, Giacomo Ferrante, Michele Frigerio, Thomas Hambye

Abstract: In models with spontaneous symmetry breaking by scalar fields in large group representations, we observe that some of the scalar masses can be loop-suppressed with respect to the naive expectation from symmetry selection rules. We present minimal models -- the $\rm{SU(2)}$ five-plet and $\rm{SU(3)}$ ten-plet -- with such accidentally light scalars, featuring compact tree-level flat directions lifted by radiative corrections. We sketch some potential applications, from stable relics and slow roll in cosmology, to hierarchy and fine-tuning problems in particle physics.

10.Gauge invariant spectral analysis of quark hadronization dynamics

Authors:Alberto Accardi, Caroline S. R. Costa, Andrea Signori

Abstract: We study the Dirac decomposition of the gauge invariant quark propagator, whose imaginary part describes the hadronization of a quark as this interacts with the vacuum, and relate each of its coefficients to a specific sum rule for the chiral-odd and chiral-even quark spectral functions. Working at first in light-like axial gauge, we obtain a new sum rule for the spectral function associated to the gauge fixing vector, and show that its second moment is in fact equal to zero. Then, we demonstrate that the first moment of the chiral-odd quark spectral function is equal in any gauge to the so-called inclusive jet mass, which is related to the mass of the particles produced in the hadronization of a quark. Finally, we present a gauge-dependent formula that connects the second moment of the chiral-even quark spectral function to invariant mass generation and final state rescattering in the hadronization of a quark.

1.Kaon and strangeonium spectrum in Regge phenomenology

Authors:Juhi Oudichhya, Keval Gandhi, Ajay Kumar Rai

Abstract: In the present work, the mass-spectra of the light mesons, the kaons ($u\overline{s}$) and strangeonium ($s\overline{s}$) is systematically studied within the framework of Regge phenomenology. Several relations between Regge slope, intercept, and meson masses are extracted with the assumption of linear Regge trajectories. Using these relations the ground state masses ($1^{1}S_{0}$ and $1^{3}S_{1}$) of the pure $s\overline{s}$ states are evaluated. Further, the Regge slopes are extracted for kaons and strangeonium to obtain the orbitally excited state masses in the ($J,M^{2}$) plane. Similarly, the values of Regge parameters are calculated in the ($n,M^{2}$) plane for each Regge trajectory and obtain the radially excited state masses of mesons lying on that Regge trajectory. We compared our obtained spectrum with the experimental observations where available and with the predictions of other theoretical approaches. Here, we predict the possible quantum numbers of several recently observed experimental states, which still require further verification, and also evaluate the higher orbital and radial excited states that may be detected in the near future. We expect our predicted results could provide valuable information for future experimental searches for missing excited kaons and strangeonium mesons.

2.Theoretical study on $Λ_c^+ \to ΛK^+\bar{K}^0$ decay and $Ξ^*(1690)$ resonance

Authors:Si-Wei Liu, Qing-Hua Shen, Ju-Jun Xie

Abstract: We present a theoretical study of $\Xi^*(1690)$ resonance in the $\Lambda_c^+ \to \Lambda K^+ \bar{K}^0$ decay, where the weak interaction part proceeds through the Cabibbo-favored process $c \to s + u\bar{d}$. Next, the intermediate two mesons and one baryon state can be constructed with a pair of $q\bar{q}$ with the vacuum quantum numbers. Finally, the $\Xi^*(1690)$ is mainly produced from the final state interactions of $\bar{K}\Lambda$ in coupled channels, and it is shown in the $\bar{K}\Lambda$ invariant mass distribution. Besides, the scalar meson $a_0(980)$ and nucleon excited state $N^*(1535)$ are also taken into account in the decaying channels $K^+\bar{K}^0$ and $K^+\Lambda$, respectively. Within model parameters, the $K^+ \bar{K}^0$, $\bar{K}^0 \Lambda$ and $K^+ \Lambda$ invariant mass distributions are calculated, and it is found that our theoretical results can reproduce well the experimental measurements, especially for the clear peak around $1690$ MeV in the $\bar{K}\Lambda$ spectrum. The proposed weak decay process $\Lambda_c^+ \to \Lambda K^+ \bar{K}^0$ and the interaction mechanism can provide valuable information on the nature of the $\Xi^*(1690)$ resonance.

3.Radiative energy loss of heavy quark through soft gluon emission in QGP

Authors:Taesoo Song, Ilia Grishmanovskii, Olga Soloveva, Elena Bratkovskaya

Abstract: The Low's theorem is applied to the soft gluon emission from heavy quark scattering in quark-gluon plasma (QGP). The QGP is described by the dynamical quasi-particle model (DQPM) which reproduces the EoS from lQCD at finite temperature and chemical potential. We show that if the emitted gluon is soft and of long wavelength, the scattering amplitude can be factorized into the scattering part and the emission part and the Slavnov-Taylor identities are satisfied in the leading order. Imposing a proper upper limit on the emitted gluon energy, we obtain the scattering cross sections of charm quark as well as the transport coefficients (momentum drag and diffusion) in the QGP with and without gluon emission.

4.Three-meson $τ$ decays involving kaons and $η$ mesons in the NJL model

Authors:M. K. Volkov, A. A. Pivovarov, K. Nurlan

Abstract: Branching fractions of decays $\tau \to K^0 \pi^- \eta\nu_\tau$, $\tau \to K^- \pi^0 \eta\nu_\tau$, $\tau \to K^-K^0 \eta\nu_\tau$ and $\tau \to K^- \eta \eta \nu_\tau$ are calculated in the $U(3)\times U(3)$ chiral NJL quark model. The contact, vector, axial-vector and pseudoscalar channels are considered. It is shown that the axial vector channel is dominant. The obtained results are in satisfactory agreement with experiment.

5.Neutrino Cross Sections: Interface of shallow- and deep-inelastic scattering for collider neutrinos

Authors:Yu Seon Jeong, Mary Hall Reno

Abstract: Neutrino experiments in a Forward Physics Facility at the Large Hadron Collider can measure neutrino and antineutrino cross sections for energies up to a few TeV. For neutrino energies below 100 GeV, the inelastic cross section evaluations have contributions from weak structure functions at low momentum transfers and low hadronic final state invariant mass. To evaluate the size of these contributions to the neutrino cross section, we use a parametrization of the electron-proton structure function, adapted for neutrino scattering, augmented with a correction to account for the partial conservation of the axial vector current, and normalized to structure functions evaluated at next-to-leading order in QCD, with target mass corrections and heavy quark corrections. We compare our results with other approaches to account for this kinematic region in neutrino cross section for energies between 10--1000 GeV on isoscalar nucleon and iron targets.

6.Axion dark matter with explicit Peccei-Quinn symmetry breaking in the axiverse

Authors:Hai-Jun Li

Abstract: It is shown that the required high quality of the Peccei-Quinn (PQ) symmetry can be a natural outcome of the multiple QCD axion models. In the axiverse, a hypothetical mass mixing between the QCD axions and axion-like particles (ALPs) can occur, which leads to an interesting phenomenon called the level crossing. In this paper, we investigate this mass mixing between one QCD axion and one ALP with the explicit PQ symmetry breaking in the early Universe. The dynamics of the axions and their cosmological evolutions when the level crossing occurs in this scenario are studied in detail. Then we focus our attention on the axion dark matter (DM) abundance. With several typical parameter sets for level crossing, we find that in the presence of the explicit PQ symmetry breaking term in the mixing, the total axion DM abundance is dominated by ALP and significantly suppressed.

7.Nonperturbative QED Processes at ELI-NP

Authors:M. Pentia, C. R. Badita, D. Dumitriu, A. R. Ionescu, H. Petrascu

Abstract: The present paper analyses the current results and pursuits the main steps required for the design of SF-QED experiments at High-Power Laser System (HPLS) of ELI-NP in Magurele, Romania. After a brief analysis of the first experiment (E-144 SLAC), which confirmed the existence of non-linear QED interactions of the high energy electrons with the photons of a laser beam, we went on to present fundamental QED processes possible to be studied at ELI-NP in a multi-photon regime. The kinematics and characteristic parameters of the laser beam interacting with electrons were presented. In the preparation of an experiment at ELI-NP, the analysis of the kinematics and dynamics of the non-linear QED interaction processes with the physical vacuum are required. Initially, the linear QED processes and the corresponding Feynman diagrams that allow to determine the amplitude of these processes are reviewed. Based on these amplitudes, the cross sections of the processes can be obtained. For multi-photon interactions it is necessary to adapt the technique of Feynman diagrams from linear QED processes to the non-linear ones, by moving to the quantum field description with dressed Dirac-Volkov states, for particles in intense EM field. They then allow evaluation of the amplitude of the physical processes and ultimately the determination of the corresponding cross section. The SF-QED processes of multi-photon interactions with strong laser fields, can be done taking into account the characteristics of the existing facilities at ELI-NP in the context of the experimental production of electron-positron-pairs and of energetic gamma-rays. We show also some upcoming experiments similar to ours, in various stages of preparation.

8.SMEFT analysis with LHeC, FCC-eh, and EIC DIS pseudodata

Authors:Chiara Bissolotti, Radja Boughezal, Kaan Simsek

Abstract: In this study, we examine the possibilities opened by upcoming high-energy deep-inelastic scattering (DIS) experiments to investigate new physics within the framework of the Standard Model Effective Field Theory (SMEFT). Specifically, we investigate the beyond-the-Standard-Model (BSM) potential of the Large Hadron-electron Collider (LHeC) and the Future Circular lepton-hadron Collider (FCC-eh), and we improve previous simulations of the Electron-Ion Collider (EIC) by incorporating $Z$-boson vertex corrections. Our fits, performed using DIS pseudodata, reveal that the LHeC and the FCC-eh can play a crucial role in resolving degeneracies observed in the parameter space of Wilson coefficients in global fits using the Higgs, diboson, electroweak, and top data. This emphasizes the significance of precision DIS measurements in advancing our understanding of new physics.

9.Probing Light Dark Matter through Cosmic-Ray Cooling in Active Galactic Nuclei

Authors:Gonzalo Herrera, Kohta Murase

Abstract: Recent observations of high-energy neutrinos from active galactic nuclei (AGN), NGC 1068 and TXS 0506+056, suggest that cosmic rays (CRs) are accelerated in the vicinity of the central supermassive black hole and high-energy protons and electrons can cool efficiently via interactions with ambient photons and gas. The dark matter density may be significantly enhanced near the central black hole, and CRs could lose energies predominantly due to scatterings with the ambient dark matter particles. We propose CR cooling in AGN as a new probe of dark matter-proton and dark matter-electron scatterings. Under plausible astrophysical assumptions, our constraints on sub-GeV dark matter can be the strongest derived to date. Some of the parameter space favored by thermal light dark matter models might already be probed with current multimessenger observations of AGN.

1.Fast evaluation of heavy-quark contributions to DIS in APFEL++

Authors:P. Risse, V. Bertone, T. Ježo, M. Klasen, K. Kovařík, F. I. Olness, I. Schienbein

Abstract: Mass-dependent quark contributions are of great importance to DIS processes. The simplified-ACOT-scheme includes these effects over a wide range of momentum transfers up to next-to-leading order in QCD. In recent years an improvement in the case of neutral current DIS has been achieved by using zero-mass contributions up to next-to-next-to-leading order (NNLO) with massive phase-space constraints. In this work, we extend this approach to the case of charged current DIS and provide an implementation in the open-source code APFEL++. The increased precision will be valuable for ongoing and future neutrino programs, the Electron-Ion-Collider and the studies of partonic substructure of hadrons and nuclei. A highly efficient implementation using gridding techniques extends the applicability of the code to the determination of parton distribution functions (PDFs).

2.$B_{(s)} \rightarrow D^{**}_{(s)}$ form factors in HQEFT and model independent analysis of relevant semileptonic decays with NP effects

Authors:Ya-Bing Zuo, Hong-Yao Jin, Jing-Ying Tian, Jia Yi, Han-Yu Gong, Ting-Ting Pan

Abstract: The form factors of $B_{(s)}$ decays into P-wave excited charmed mesons (including $D^*_0(2300)$, $D_1(2430)$, $D_1(2420)$, $D^*_2(2460)$ and their strange counterparts, denoted generically as $D^{**}_{(s)}$) are systematically calculated via the QCD sum rules in the framework of heavy quark effective field theory (HQEFT). We consider contributions up to the next leading order of heavy quark expansion and give all the relevant form factors, including the scalar and tensor ones which are only related to possible new physics effects. The expressions of form factors in terms of several universal wave functions are derived via the heavy quark expansion. These universal functions can be evaluated through QCD sum rules. Then the numerical results of form factors are presented. With the form factors given here, a model independent analysis of relevant semileptonic decays $B_{(s)} \rightarrow D^{**}_{(s)} l \bar{\nu}_l$ is performed, including the contributions from possible new physics effects. Our predictions for the differential decay widths, branching fractions and the ratios of branching fractions $R(D^{**}_{(s)})$ may be tested by more precise experiments in the future.

3.Higher molecular $P_{ψs}^{Λ/Σ}$ pentaquarks arising from the $Ξ_c^{(\prime,*)}\bar D_1/Ξ_c^{(\prime,*)}\bar D_2^*$ interactions

Authors:Fu-Lai Wang, Xiang Liu

Abstract: The discoveries of the $P_{\psi s}^\Lambda(4459)$ and $P_{\psi s}^\Lambda(4338)$ as the potential $\Xi_c\bar D^{(*)}$ molecules have sparked our curiosity in exploring a novel class of molecular $P_{\psi s}^{\Lambda/\Sigma}$ pentaquarks. In this study, we carry out an investigation into the higher molecular pentaquarks, specifically focusing on the $P_{\psi s}^{\Lambda/\Sigma}$ states arising from the $\Xi_c^{(\prime,*)}\bar D_1/\Xi_c^{(\prime,*)}\bar D_2^*$ interactions. Our approach employs the one-boson-exchange model, incorporating both the $S$-$D$ wave mixing effect and the coupled channel effect. Our numerical results suggest that the $\Xi_c\bar D_1$ states with $I(J^P)=0({1}/{2}^+,\,{3}/{2}^+)$, the $\Xi_c\bar D_2^*$ states with $I(J^P)=0({3}/{2}^+,\,{5}/{2}^+)$, the $\Xi_c^{\prime}\bar D_1$ states with $I(J^P)=0({1}/{2}^+,\,{3}/{2}^+)$, the $\Xi_c^{\prime}\bar D_2^*$ states with $I(J^P)=0({3}/{2}^+,\,{5}/{2}^+)$, the $\Xi_c^{*}\bar D_1$ states with $I(J^P)=0({1}/{2}^+,\,{3}/{2}^+,\,{5}/{2}^+)$, and the $\Xi_c^{*}\bar D_2^*$ states with $I(J^P)=0({1}/{2}^+,\,{3}/{2}^+,\,{5}/{2}^+,\,{7}/{2}^+)$ can be recommended as the most promising molecular $P_{\psi s}^\Lambda$ pentaquark candidates, and there may exist the potential molecular $P_{\psi s}^\Sigma$ pentaquark candidates for several isovector $\Xi_c^{(\prime,*)}\bar D_1/\Xi_c^{(\prime,*)}\bar D_2^*$ states. With the higher statistical data accumulation at the LHCb's Run II and Run III status, there is the possibility that our predicted $P_{\psi s}^{\Lambda/\Sigma}$ states can be detected through the weak decay of the $\Xi_b$ baryon, especially in hunting for the predicted $P_{\psi s}^\Lambda$ states.

4.System size dependence of pre-equilibrium and applicability of hydrodynamics in heavy-ion collisions

Authors:Victor E. Ambruş, Sören Schlichting, Clemens Werthmann

Abstract: We simulate the space-time dynamics of high-energy collisions based on a microscopic kinetic description, in order to determine the range of applicability of an effective description in relativistic viscous hydrodynamics. We find that hydrodynamics provides a quantitatively accurate description of collective flow when the average inverse Reynolds number $\mathrm{Re}^{-1}$ is sufficiently small and the early pre-equilibrium stage is properly accounted for. By determining the breakdown of hydrodynamics as a function of system size and energy, we find that it is quantitatively accurate in central lead-lead collisions at LHC energies, but should not be used in typical proton-lead or proton-proton collisions, where the development of collective flow can not accurately be described within hydrodynamics.

5.Repercussions of the Peccei-Quinn axion on QCD

Authors:Gerrit Schierholz

Abstract: The axion, originally postulated by Peccei and Quinn to solve the strong CP problem, has become of great interest in particle and astroparticle phenomenology. Yet it has a problem. It is widely assumed that the axion leaves the nonperturbative features of QCD, such as the axial anomaly and chiral symmetry breaking, unscathed. This is, however, not the case. It turns out that the anomalous coupling of the axion to the gauge bosons can be integrated partially, leaving behind a path integral extending over topologically trivial gauge potentials only. This has far reaching consequences. We conclude that the Peccei-Quinn axion extension of the Standard Model is not a viable theory.

6.Axion search via Coulomb-assisted quantum vacuum birefringence

Authors:Stefan Evans, Ralf Schützhold

Abstract: We study the impact of axions or axion-like particles on birefringent (i.e., polarization changing) scattering of x-ray photons at the Coulomb field of nuclei superimposed by optical lasers of ultra-high intensity. Applying the specifications of the Helmholtz International Beamline for Extreme Fields (HIBEF), we find that this set-up can be more sensitive than previous experiments such as PVLAS in a large domain of parameter space. Furthermore, by changing the pump and probe laser orientations and frequencies, one can scan different axion masses.

7.Predictions of the hybrid mesons with exotic quantum numbers $J^{PC}=2^{+-}$

Authors:Qi-Nan Wang, Ding-Kun Lian, Wei Chen

Abstract: We study the non-strange and strangeonium light hybrid mesons with $J^{PC}=2^{+-}$ by using the method of QCD sum rules. The local hybrid interpolating currents with three Lorentz indices are constructed to couple to such exotic quantum numbers. We calculate the correlation functions up to dimension eight condensates at the leading order of $\alpha_{s}$. In our results, the masses of the non-strange $b_2$ and $h_2$ hybrids are about $2.65~\mathrm{GeV}$, while that of the strangeonium $h_2^\prime$ hybrid is about $2.74~\mathrm{GeV}$. Such exotic $2^{+-}$ hybrids can be generated through both the two-gluon and three-gluon emission processes in the radiative decays of $\chi_{cJ}$. Moreover, these hybrid mesons may be detectable due to their peculiar decay behaviors and small decay widths. Using the high-statistics data samples of $\psi(3686)$ in BESIII and BelleII, it is possible to hunt for such hybrid states through the partial wave analyses in the $b_2\to\omega/a_1/h_1/a_2\pi\to4\pi$, $h_2\to\rho\pi\to3\pi$ and $h_2\to b_1\pi\to5\pi$ processes.

8.Standard Model Higgs inflation supplemented by minimal dark matter

Authors:Shinsuke Kawai, Nobuchika Okada, Qaisar Shafi

Abstract: Renormalisation group analysis with the present measurements of the top quark mass $m_t = 172.69\pm 0.30$ GeV indicates that the Standard Model (SM) Higgs potential becomes unstable at energy scales $\sim 10^{10}$ GeV. This may be interpreted as hinting at new particles at high energy. The minimal extension of the SM that can avoid this instability while leaving the SM Higgs as the sole scalar particle of the theory is obtained by adding suitable fermions to the SM. These fermions are good dark matter candidates and the model is known as the minimal dark matter model. We revisit the inflationary scenario based on the minimal dark matter model, taking into account updated parameter constraints and recent understanding of reheating dynamics. We explore the model with different values of the right-handed neutrino mass and find that the cosmological prediction is insensitive to such details. We obtained a spectral index of the cosmic microwave background $n_s=9.672$ and a tensor-to-scalar ratio $r=0.0031$ as a robust prediction of this scenario.

9.Analysis of double-$J/ψ$ production in $Z$ decay at next-to-leading-order QCD accuracy

Authors:Cong Li, Zhan Sun, Gui-Yuan Zhang

Abstract: In this article, we study in detail the double-$J/\psi$ yield through $Z$ decay at the next-to-leading-order (NLO) QCD accuracy within the nonrelativistic QCD factorization. At the tree level, the pure QCD diagrams predict a branching ratio of $\mathcal{B}_{Z \to J/\psi+J/\psi} \sim 10^{-12}$; however, the inclusion of the QED diagrams would augment this prediction by approximately 2-3 orders of magnitude. After incorporating the QCD corrections, the QCD results exhibit a considerable increase, whereas the QED results undergo a substantial reduction. Combing the QCD and QED contributions at NLO in $\alpha_s$, it is observed that the prediction of $\mathcal{B}_{Z \to J/\psi+J/\psi}=(1.110^{+0.334+0.054}_{-0.241-0.001})\times 10^{-10}$, which displays a fairly steady dependence on the renormalization scale, is significantly lower than the upper limits released by CMS.

10.Longitudinal flow decorrelation in heavy-ion collision at RHIC energies using a multi-phase transport model

Authors:Prabhupada Dixit, Md. Nasim

Abstract: We present a comprehensive study on the longitudinal flow decorrelation in heavy-ion collisions at the RHIC Beam Energy Scan (BES) energies, spanning from $\sqrt{s_{NN}}$ = 11.5 to 200 GeV in Au+Au collisions, using the A Multi-Phase Transport (AMPT) model. Our investigation entails measuring the second and third order factorization ratios ($r_{2}$ and $r_{3}$) across all these energies. We observed that the decorrelation is stronger at lower energies compared to higher collision energies, with this energy dependence trend being more prominent in $r_{3}$. Additionally, we analyze the contributions of flow-plane and flow magnitude decorrelation to the overall decorrelation phenomenon. Notably, our findings reveal that flow plane decorrelation exhibits a dominant contribution compared to flow magnitude decorrelation. Moreover, we incorporate a recently proposed observable, the four particle cumulant ($T_{2}$), which remains resilient to non-flow effects and exhibits sensitivity to different decorrelation patterns. Through the measurement of $T_{2}$, we consistently observe an S-shaped or torqued decorrelation across all energy ranges.

11.Asymptotic mass limit of large fully-heavy compact multiquarks

Authors:M. C. Gordillo, J. M Alcaraz-Pelegrina

Abstract: The properties of fully-heavy arrangements including a number of quarks between 5 and 12 were calculated within the framework of a constituent quark model by using a diffusion Monte Carlo technique. We considered only clusters in which all the quarks had the same mass, and whose number of particles and antiparticles were adequate to produce color singlets. All the multiquarks were in their lowest possible values of $L^2$ and $S^2$ operators. This means that we considered only color-spin wavefunctions that were antisymmetric with respect to the interchange of {\em any} two quarks of the same type. We found that in both all-$c$ and all-$b$ multiquarks, the mass per particle levels off for arrangements with a number of quarks larger of equal than six. The analysis of their structure implies that the fully-heavy multiquarks are compact structures.

12.Parton cascades at DLA: the role of the evolution variable

Authors:Carlota Andrés, Liliana Apolinário, Néstor Armesto, André Cordeiro, Fabio Dominguez, José Guilherme Milhano

Abstract: While experimental studies on jet quenching have achieved a large sophistication, the theoretical description of this phenomenon still misses some important points. One of them is the interplay of vacuum-like emissions, usually formulated in momentum space, with the medium induced ones that demand an interplay with a space-time picture of the medium and thus must be formulated in position space. A unified description of both vacuum and medium-induced emissions is lacking. In this work, we compute the tree-level probability of a double gluon emission in vacuum, and identify the enhanced phase-space regions for each diagram, corresponding to different configurations of the parton cascade. This calculation provides a parametric form for the formation times associated with each diagram, highlighting the equivalence of various ordering variables at double logarithmic accuracy. This equivalence is further explored by building a toy Monte-Carlo parton shower ordered in formation time, virtuality, transverse momentum, and angle. Aiming at a link with jet substructure, we compute the Lund Plane distributions and trajectories for each ordering prescription. We also compute the distributions in number of splittings and final partons, with the goal of clarifying the differences to be expected from the different ordering variables and the vetoes that must be implemented at Monte Carlo level to conserve energy-momentum, which turn out to have a sizeable influence on the shower's evolution.

13.Neutrino decoupling and the transition to cold dark matter

Authors:Roman Schnabel

Abstract: About 40 years ago, the neutrino was ruled out as the dark matter particle based on several arguments. Here I use the well-established concept of quantum uncertainties of position and momentum to describe the decoupling of neutrinos from the primordial plasma, which took place about half a second after the Big Bang. In this way I show that the main arguments against the neutrino are either wrong or have loopholes, and conclude that the neutrino urgently needs to be reconsidered, not as a 'hot', but as the 'cold' dark matter particle.

14.Three-loop master integrals for H+jet production at N$^3$LO: Towards the non-planar topologies

Authors:Dhimiter D. Canko, Nikolaos Syrrakos

Abstract: We discuss the recent progress that has been made towards the computation of three-loop non-planar master integrals relevant to next-to-next-to-next-to-leading-order (N$^3$LO) corrections to processes such as H+jet production at the LHC. We describe the analytic structure of these integrals, as well as several technical issues regarding their analytic computation using canonical differential equations. Finally, we comment on the remaining steps towards the computation of all relevant three-loop topologies and their application to amplitude calculations.

15.$k-$Dependent Dark Matter

Authors:Parisa Arabameri, Zahra Davari, Nima Khosravi

Abstract: With the emersion of precise cosmology and the emergence of cosmic tensions, we are faced with the question of whether the simple model of cold dark matter needs to be extended and whether doing so can alleviate the tensions and improve our understanding of the properties of dark matter. In this study, we investigate one of the generalized models of dark matter so that the behavior of this dark matter changes according to the scale of $k$. In large scales (small $k$'s), the dark matter is cold, while it becomes warm for small scales (large $k$'s). This behavior is modeled phenomenologically for two different scenarios. We show that the $S_8$ tension can be alleviated, but the $H_0$ tension becomes milder while not too much.

16.Towards UV-Models of Kinetic Mixing and Portal Matter IV: Quartification

Authors:Thomas G. Rizzo

Abstract: As is well-known, Trinification, \ie, the extension of the Standard Model (SM) to $[SU(3)]^3=SU(3)_c\times SU(3)_L\times SU(3)_R$ as occurs in $E_6$ models, allows for a partial unification of the gauge forces even though quarks and leptons remain in separate multiplets so that no heavy gauge or scalar fields exist which can generate proton decay. The extension of this idea to Quartification, by including an additional $SU(3)'$ factor, has also been considered in the literature maintaining the basic attributes of Trinification but now allowing, \eg, for a more symmetric treatment of quarks and leptons at the price of new matter fields and gauge interactions. In this paper, we will consider this $SU(3)'$ to be the `dark' gauge group, now containing the familiar $U(1)_D$ subgroup, under which the SM fields are all neutral, which is associated with kinetic mixing (KM) and the existence of a light, $\lsim 1 $ GeV dark photon. This setup naturally predicts the existence of color-singlet portal matter (PM) fields, carrying both electromagnetic and $U(1)_D$ dark charges, that are necessary to generate this KM at the 1-loop level and whose masses are directly tied with those of the many new gauge bosons that originate from the extended gauge sector. In this paper, after a discussion of the detailed structure of this model, we present a broad survey of the collider phenomenology of the large set of new fields that must necessarily arise from this setup in a simplified version involving only a single generation of fermions. We demonstrate that several new signatures may be anticipated at the LHC as well as at future hadron and lepton colliders if such models are realized in nature.

17.The linear response theory approach to the sub-GeV dark matter in the Sun

Authors:Zheng-Liang Liang, Ping Zhang

Abstract: In recent years, the importance of the electronic in-medium effect in the sub-GeV dark matter (DM) direct detection has been recognized and a coherent formulation of the DM-electron scattering based the linear response theory has been well established in the literature. In this paper, we apply the formulation to the scattering between DM particles and solar medium, and it is found that the dynamic structure factor inherently incorporate the particle-particle scattering and in-medium effect. Using this tool and taking a benchmark model as an example, we demonstrate how the in-medium effect affect the scattering of DM particles in the Sun, in both the heavy and light mediator limit. Formulae derived in this work lay the foundation for accurately calculating the spectra of solar-accelerated DM particles, which is of particular importance for the detection of DM particles via plasmon in semiconductor targets.

18.Hilbert series for ALP EFTs

Authors:Christophe Grojean, Jonathan Kley, Chang-Yuan Yao

Abstract: Axions and axion-like particles (ALPs) are ubiquitous in popular attempts to solve supercalifragilisticexpialidocious puzzles of Nature. A widespread and vivid experimental programme spanning a vast range of mass scales and decades of couplings strives to find evidence for these elusive but theoretically well-motivated particles. In the absence of clear guiding principle, effective field theories (EFTs) prove to be an efficient tool in this experimental quest. Hilbert series technologies are a privileged instrument of the EFT toolbox to enumerate and classify operators. In this work, we compute explicitly the Hilbert series capturing the interactions of a generic ALP to the Standard Model particles above and below the electroweak symmetry scale, which allow us to build bases of operators up to dimension-8. In particular, we revealed a remarkable structure of the Hilbert series that isolates the shift-symmetry breaking and preserving interactions. Furthermore, we provide an ancillary file of the Hilbert series up to dimension 15 to supplement our findings, which can be used for further analysis and exploration.

19.Search for Light Dark Photon in the Forward Experiments at the LHC

Authors:Yeong Gyun Kim, Kang Young Lee, Soo-hyeon Nam

Abstract: We investigate detection possibility of light dark photon in the forward experiments at the LHC, such as the SND@LHC and the FASER experiments. We assume that the dark photon mass is smaller than twice of the electron mass. Then the dark photon is long-lived and copiously produced through a neutral pion decay. Such dark photons would easily pass through 100 m of rock in front of the forward experiments and the detector targets, but some portion of them could be converted into an electron-positron pair inside the detector leaving an isolated electromagnetic shower as a new physics signature of the dark photon. Our estimation shows that in the range of kinetic mixing parameter $4\times10^{-5} \lesssim \epsilon \lesssim 2\times10^{-1}$, more than 10 signal events of the dark photon can be produced assuming 150 fb$^{-1}$ integrated luminosity.

20.Large Rapidity Gaps in proton-nucleus interaction

Authors:V. A. Khoze, M. G. Ryskin

Abstract: We analyse the cross-section of events with Large Rapidity Gaps observed in proton-lead collisions by the CMS collaboration. The role of the transverse size of elementary $pN$ amplitude is discussed. We emphasize that the cross-section of incoming proton dissociation caused by the photon radiated off the lead ion is close to the value of $d\sigma/d\Delta\eta^F$ measured by the CMS, and it is not clear why there is no room in the data for the Pomeron-induced contribution

21.Gauging the cosmic ray muon puzzle with the Forward Physics Facility

Authors:Sergio J. Sciutto for the FPF Initiative, Luis A. Anchordoqui for the FPF Initiative, Carlos Garcia Canal for the FPF Initiative, Felix Kling for the FPF Initiative, Jorge F. Soriano for the FPF Initiative

Abstract: We investigate the observed muon deficit in air shower simulations when compared to ultrahigh-energy cosmic ray (UHECR) data. Gleaned from the observed enhancement of strangeness production in ALICE data, the associated $\pi \leftrightarrow K$ swap is taken as a cornerstone to resolve the muon puzzle via its corresponding impact on the shower evolution. We develop a phenomenological model in terms of the $\pi \leftrightarrow K$ swapping probability $F_s$. We provide a parametrization of $F_s (E^{\rm (proj)}, \eta)$ that can accommodate the UHECR data, where $E^{\rm (proj)}$ is the projectile energy and $\eta$ the pseudorapidity. We also explore a future game plan for model improvement using the colossal amount of data to be collected by LHC neutrino detectors at the Forward Physics Facility (FPF). We calculate the corresponding sensitivity to $F_s$ and show that the FPF experiments will be able to probe the model phase space.

1.A Monte Carlo study of multiplicity fluctuations in proton-proton collisions at $\sqrt{s}=$~7~TeV

Authors:Valeria Zelina Reyna Ortiz, Maciej Rybczynski, Zbigniew Wlodarczyk

Abstract: With large volumes of data available at LHC, it has possible to study the multiplicity distributions. It is interesting as well to check how well event generators can describes the properties and the behavior of multi-particle production processes. In this paper, we analyse the oscillatory behavior of modified combinants in proton-proton collisions at centre of mass energy of 7 TeV.

2.Probing new physics with polarized $τ$ and $Λ_c$ in quasielastic $ν_τ\!+\!n\!\to\! τ^-\!+\!Λ_c$ scattering process

Authors:Ya-Ru Kong, Li-Fen Lai, Xin-Qiang Li, Xin-Shuai Yan, Ya-Dong Yang

Abstract: The absence of semitauonic decays of charmed hadrons makes the decay processes mediated by the quark-level $c\to d \tau^+ \nu_{\tau}$ transition inadequate for probing a generic new physics (NP) with all kinds of Dirac structures. To fill in this gap, we consider in this paper the quasielastic neutrino scattering process $\nu_{\tau}+n\to \tau^-+\Lambda_c$, and propose searching for NP through the polarizations of the $\tau$ lepton and the $\Lambda_c$ baryon. In the framework of a general low-energy effective Lagrangian, we perform a comprehensive analysis of the (differential) cross sections and polarization vectors of the process both within the Standard Model and in various NP scenarios, and scrutinize possible NP signals. We also explore the influence on our findings due to the uncertainties and the different parametrizations of the $\Lambda_c \to N$ transition form factors, and show that they have become one of the major challenges to further constrain possible NP through the quasielastic scattering process.

3.Analysis of the higher twist GTMD $F_{31}$ for proton in the light-front quark-diquark model

Authors:Shubham Sharma, Harleen Dahiya

Abstract: In the light-front quark-diquark model (LFQDM), the higher twist generalized transverse momentum dependent distribution (GTMD) $F_{31}(x, {\bf p_\perp},{\bf \Delta_\perp})$ for the proton has been analyzed. We have derived the GTMD overlap equation by the analysis of GTMD correlator, employing the light-front wave functions in both the scalar and vector diquark situations. With the relevant 2-D and 3-D figures, the behavior of GTMD $F_{31}(x, {\bf p_\perp},{\bf \Delta_\perp})$ with variations in its variables has been illustrated. Further, on applying the transverse momentum dependent distribution (TMD) limit on GTMD $F_{31}(x, {\bf p_\perp},{\bf \Delta_\perp})$, the expression of TMD $f_3(x, {\bf p_\perp})$ has been obtained.

4.GENEVA Monte Carlo: status and new developments

Authors:Marinelli Giulia

Abstract: We review GENEVA Monte Carlo framework, that combines three theoretical tools used for QCD precise predictions into a single structure. In this talk we highlight its main features, discussing some new improvements involving both colour singlet productions, as well as for the production of final states with heavy coloured partons and jets.

5.Charm-Meson $t$-channel Singularities in an Expanding Hadron Gas

Authors:Eric Braaten, Roberto Bruschini, Li-Ping He, Kevin Ingles, Jun Jiang

Abstract: We study the time evolution of the numbers of charm mesons after the kinetic freezeout of the expanding hadron gas produced by the hadronization of the quark-gluon plasma from a central heavy-ion collision. The $\pi D$ reaction rates have contributions from a $D^\ast$ resonance in the $s$ channel. The $\pi D^\ast$ reaction rates are enhanced by $t$-channel singularities from an intermediate $D$. The contributions to reaction rates from $D^\ast$ resonances and $D$-meson $t$-channel singularities are sensitive to thermal mass shifts and thermal widths. In the expanding hadron gas, the $t$-channel singularities are regularized by the thermal $D$ widths. After kinetic freezeout, the thermal $D$ widths are dominated by coherent pion forward scattering. The contributions to $\pi D^\ast$ reaction rates from $t$-channel singularities are inversely proportional to the pion number density, which decreases to 0 as the hadron gas expands. The $t$-channel singularities produce small but significant changes in charm-meson ratios from those predicted using the known $D^\ast$-decay branching fractions.

6.Low-Scale Leptogenesis with Low-Energy Dirac CP-Violation

Authors:Alessandro Granelli, Silvia Pascoli, Serguey T. Petcov

Abstract: We study the freeze-in scenario of leptogenesis via oscillations within the type-I seesaw model with two quasi-degenerate heavy Majorana neutrinos $N_{1,\,2}$ having masses $M_2 > M_1 \sim (0.1-100)\,\text{GeV}$, $(M_2-M_1)/M_1 \ll 1$, focusing on the role of the CP-violation provided by the Dirac phase $\delta$ of the Pontecorvo-Maki-Nakagawa-Sakata lepton mixing matrix. We find that viable leptogenesis can be due solely to CP-violating values of $\delta$ and that the $N_{1,\,2}$ total mixing squared $\Theta^2=\sum_\alpha\Theta^2_\alpha$ needed is within the reach of future experiments, $\Theta_\alpha$ parameterising the coupling to the charged lepton $\alpha=e,\,\mu,\,\tau$. Furthermore, the required parameter space differs from that associated with additional Casas-Ibarra sources of CP-violation. Future determination of $\delta$, $\Theta^2$ and/or the ratios $\Theta_\tau^2:\Theta^2_\mu:\Theta^2_e$ would provide a critical test of the considered scenario.

7.NNLL Resummation for Projected Three-Point Energy Correlator

Authors:Wen Chen, Jun Gao, Yibei Li, Zhen Xu, Xiaoyuan Zhang, Hua Xing Zhu

Abstract: The projected energy correlator measures the energy deposited in multiple detectors as a function of the largest angular distance $x_L = (1 - \cos\chi_L)/2$ between detectors. The collinear limit $x_L\to 0$ of the projected energy correlator is particularly interesting for understanding the jet-substructures, while the large logarithms of $x_L$ could potentially spoil the perturbation theory and must be resummed. As a necessary ingredient for its resummation at next-to-next-to-leading logarithmic (NNLL) accuracy, we calculate the two-loop jet functions for the projected three-point energy correlator (E3C), using direct integration method and the parameter space Integration-by-Part (IBP) method. We then present the NNLL resummation for $e^+e^-$ annihilation and an approximate NNLL resummation for $pp\rightarrow jj$ process, where the two-loop hard constant is estimated in the latter case. The convergence is improved and the hadronization effect in the collinear limit is suppressed when considering the ratio of E3C distribution to two-point energy-energy correlator (EEC). Our results show potential in precision determination of strong coupling constant using energy correlators from both $e^+e^-$ data and $pp$ data.

1.Dark baryon from pure Yang-Mills theory and its GW signature from cosmic strings

Authors:Masaki Yamada, Kazuya Yonekura

Abstract: We point out that SO($2N$) pure Yang-Mills theory provides a candidate for dark matter (DM) without the explicit need to impose any additional symmetry. The DM candidate is a particular type of glueball, which we refer to as a baryonic glueball, that is naturally stable for a moderately large $N$. In this case, the intercommutation probability of cosmic strings (or macroscopic color flux tubes) is quite low, which offers characteristic gravitational wave signals to test our model. In particular, our model can simultaneously account for both abundance of DM and the recently reported gravitational wave signals detected in pulsar timing array experiments, including NANOGrav.

2.Transformation of transverse momentum distributions from Parton Branching to Collins-Soper-Sterman framework

Authors:Armando Bermudez Martinez

Abstract: Two main frameworks for defining transverse momentum dependent (TMD) parton densities are the Collins-Soper-Sterman (CSS) formalism, and the Parton Branching (PB) approach. While PB-TMDs have an explicit dependence on a single scale which is used to evolve PB-TMDs in momentum space, TMDs defined in CSS formalism present a double-scale evolution in renormalization and rapidity scales, via a pair of coupled evolution equations. In this letter I leverage the Collins-Soper kernel determined from simulated Drell Yan transverse momentum spectra using PB-TMDs, and provide, for the first time, the transformation of TMD parton distributions from the PB framework to the CSS formalism. The evolved PB-TMDs in $b$-space are compared to the recently released, unpolarized TMD distribution ART23.

3.Renormalization Group Evolution with Scalar Leptoquarks

Authors:Sumit Banik, Andreas Crivellin

Abstract: Leptoquarks are theoretically well-motivated and have received increasing attention in recent years as they can explain several hints for physics beyond the Standard Model. In this article, we calculate the renormalisation group evolution of models with scalar leptoquarks. We compute the anomalous dimensions for all couplings (gauge, Yukawa, Higgs and leptoquarks interactions) of the most general Lagrangian at the two-loop level and the corresponding threshold corrections at one-loop. The most relevant analytic results are presented in the Appendix, while the notebook containing the full expressions can be downloaded at In our phenomenological analysis, we consider some exemplary cases with focus on gauge and Yukawa coupling unification.

4.Collins-type Energy-Energy Correlators and Nucleon Structure

Authors:Zhong-Bo Kang, Kyle Lee, Ding Yu Shao, Fanyi Zhao

Abstract: We generalize the conventional Energy-Energy Correlator (EEC) to include the azimuthal angle dependence, so to define azimuthal angle dependent EEC observables. We study this new EEC observable in $e^+e^-$ and semi-inclusive deep inelastic scattering (SIDIS). In the back-to-back region, we find that the azimuthal angle dependent EEC is sensitive to both the unpolarized EEC jet function and a Collins-type EEC jet function. While the unpolarized EEC jet function is related to the unpolarized transverse momentum dependent (TMD) fragmentation function, the Collins-type EEC jet function is connected with the Collins fragmentation function. We further demonstrate how the new observables allow us to access to the 3D structure of nucleons, especially the spin-dependent ones.

1.Chemical freeze-out parametrization with mean field repulsive hadron resonance gas model

Authors:Sunny Kumar Singh, Nachiketa Sarkar, Deeptak Biswas

Abstract: We have examined the chemical freeze-out surface of the heavy-ion collision experiments within an interacting hadron resonance gas model. By considering repulsive interaction among hadrons in the mean-field level, we have suitably parameterized the freeze-out surface by fitting the yield data of mid-rapidity for the most central collision, for the collision energy available in AGS, RHIC (BES), and LHC programs. To suitably account for the repulsive interaction among mesons and (anti-) baryons, we have introduced phenomenological parameters $K_M$ and $K_B$ in the freeze-out parametrization. Although a finite value of these two parameters seem to be necessary to have an improved normalized \emph{chi-square}, the effect on the rest of the parameters like temperature and relevant chemical potentials seem to be within the standard variance.

2.Towards an integrated determination of proton, deuteron and nuclear PDFs

Authors:Tanjona Rabemananjara

Abstract: We present progress towards a unified framework enabling the simultaneous determination of the parton distribution functions (PDFs) of the proton, deuteron, and nuclei up to lead $(^{208}\rm{Pb})$. Our approach is based on the integration of the fitting framework underlying the nNNPDF3.0 determination of nuclear PDFs into that adopted for the NNPDF4.0 global analysis of proton PDFs. Our work paves the way toward a full integrated global analysis of non-perturbative QCD -- a key ingredient for the exploitation of the scientific potential of present and future nuclear and particle physics facilities such as the Electron-Ion Collider (EIC).

3.QCD effective charges from low-energy neutrino structure functions

Authors:Tanjona Rabemananjara

Abstract: We present a new perspective on the study of the behavior of the strong coupling $\alpha_s(Q^2)$ -- the fundamental coupling underlying the interactions between quarks and gluons as described by the Quantum Chromodynamics (QCD) -- in the low-energy infrared (IR) regime. We rely on the NNSF$\nu$ determination of neutrino-nucleus structure functions valid for all values of $Q^2$ from the photoproduction to the high-energy region to define an effective charge following the the Gross-Llewellyn Smith (GLS) sum rule. As a validation, our predictions for the low-energy QCD effective charge are compared to experimental measurements provided by JLab.

4.Reheating and Leptogenesis after Vector inflation

Authors:Simon Cléry IJCLab, Orsay, Pascal Anastasopoulos Vienna, OAW, Yann Mambrini IJCLab, Orsay

Abstract: We study the reheating and leptogenesis in the case of a vector inflaton. We concentrate on particle production during the phase of oscillating background, especially gravitational production induced by the presence of non-minimal coupling imposed by an isotropic and homogeneous Universe. Including processes involving the exchange of graviton, we then extend our study to decay into fermions via direct or anomalous couplings. The necessity of non-minimal gravitational coupling and the gauge nature of couplings to fermions implies a much richer phenomenology than for a scalar inflaton.

5.Synergies of Drell-Yan, beauty, top, and Z observables in MFV-SMEFT

Authors:Cornelius Grunwald, Gudrun Hiller, Kevin Kröninger, Lara Nollen

Abstract: The Standard Model Effective Field Theory (SMEFT) is a powerful tool to search for new physics in a model-independent way. We explore the synergies arising from different types of observables in a combined, global SMEFT fit. Specifically, we investigate the combination of top-quark measurements, $b\to s$ flavor changing neutral current transitions, $Z\to b \bar b$ and $Z\to c \bar c$, as well as Drell-Yan data from the LHC. We also examine the impact of Minimal Flavor Violation (MFV) as a flavor pattern in the global fit. We find that the combination of high-p$_T$ with flavor physics observables provides powerful synergies that significantly improve the fit and enable more precise tests of various SMEFT operators. By incorporating different observables, we are able to remove flat directions in the parameter space and infer on the flavor structure based on the MFV parameterization. In particular, we find that MFV significantly strengthens the constraints in comparison to a flavor-specific approach. Furthermore, our analysis yields a prediction for the dineutrino branching ratios ${\cal{B}}(B \to K^{(*)} \nu \bar \nu)$ within MFV, which can be tested experimentally at Belle II.

6.A comparative study of different approaches for heavy quark energy loss, based on the latest experimental data

Authors:Marjan Rahimi Nezhad, Fatemeh Taghavi Shahri, Sharareh Mehrabi Pari, Kurosh Javidan

Abstract: This paper presents a comparative analysis of three distinct methods used to calculate the collisional energy loss of heavy quarks in Quark-Gluon Plasma. The study focuses on the calculation of the nuclear suppression factor of charm quarks in Pb-Pb collisions at $\sqrt{S_{NN}} = 5.02$ TeV. All three models are examined using the same numerical evolution based on the well-known Fokker-Planck equation by considering critical phenomena like a non-equilibrium state at the onset of heavy ion collision. The outcomes of each approach are compared with the latest data from ALICE and ATLAS experiments spanning from 2018 to 2022. This study aims to compare the degree of agreement between each approach and recently obtained experimental data, in the intermediate and high $P_T$ regions.

7.Decoherence effects on lepton number violation from heavy neutrino-antineutrino oscillations

Authors:Stefan Antusch, Jan Hajer, Johannes Rosskopp

Abstract: We study decoherence effects and phase corrections in heavy neutrino-antineutrino oscillations (NNOs), based on quantum field theory with external wave packets. Decoherence damps the oscillation pattern, making it harder to resolve experimentally. Additionally, it enhances lepton number violation (LNV) for processes in symmetry-protected low-scale seesaw models by reducing the destructive interference between mass eigenstates. We discuss a novel time-independent shift in the phase and derive formulae for calculating decoherence effects and the phase shift in the relevant regimes, which are the no dispersion regime and transverse dispersion regime. We find that the phase shift can be neglected in the parameter region under consideration since it is small apart from parameter regions with large damping. In the oscillation formulae, decoherence can be included by an effective damping parameter. We discuss this parameter and present averaged results, which apply to simulations of NNOs in the dilepton-dijet channel at the HL-LHC. We show that including decoherence effects can dramatically change the theoretical prediction for the ratio of LNV over LNC events.

8.In-medium gluon radiation spectrum with all-order resummation of multiple scatterings in longitudinally evolving media

Authors:Carlota Andres, Liliana Apolinário, Fabio Dominguez, Marcos Gonzalez Martinez

Abstract: Over the past years, there has been a sustained effort to systematically enhance our understanding of medium-induced emissions occurring in the quark-gluon plasma, driven by the ultimate goal of advancing our comprehension of jet quenching phenomena. To ensure meaningful comparisons between these new calculations and experimental data, it becomes crucial to model the interplay between the radiation process and the evolution of the medium parameters, typically described by a hydrodynamical simulation. This step presents particular challenges when dealing with calculations involving the resummation of multiple scatterings, which have been shown to be necessary for achieving an accurate description of the in-medium emission process. In this paper, we extend our numerical calculations of the fully-resummed gluon spectrum to account for longitudinally expanding media. This new implementation allows us to quantitatively assess the accuracy of previously proposed scaling laws that establish a correspondence between an expanding medium and a "static equivalent". Additionally, we show that such scaling laws yield significantly improved results when the static reference case is replaced by an expanding medium with the temperature following a simple power-law decay. Such correspondence will enable the application of numerical calculations of medium-induced energy loss in realistic evolving media for a broader range of phenomenological studies.

9.Diffractive Deep Inelastic Scattering in the Dipole Picture at Next-to-Leading Order

Authors:G. Beuf, H. Hänninen, T. Lappi, H. Mäntysaari, Y. Mulian

Abstract: We calculate the contribution from the $q \bar q g$ state production to the diffractive cross sections in deep inelastic scattering at high energy. The obtained cross section is finite by itself, and consists a part of the full next-to-leading order result for the diffractive structure functions. Our calculation for the diffractive structure functions is performed using exact kinematics, under the shockwave approximation of the scattering process. Once the calculation is completed, we show that the previously known behaviour at the high-$Q^2$ and large-$M_X^2$ regime can be extracted from our results by taking the appropriate limits. Furthermore, we discuss the steps required to obtain the complete next-to-leading order results for the structure functions in the color glass condensate (CGC) formalism, and the application of these results to phenomenology.

1.Anomalies in Weak Decays of Hadrons Containing a b Quark

Authors:Aidos Issadykov, Mikhail A. Ivanov

Abstract: A brief review of the current state of observed deviations of theoretical predictions from experimental data in semileptonic decays of $B$ and $B_c$ mesons is given. A theoretical analysis of these decays is carried out, taking into account the effects of new physics, which appear due to the introduction of new four-fermion operators, which are absent in the basis of the Standard Model (SM) operators. The necessary form factors are calculated within the framework of the covariant quark model developed in our papers.

2.$ Λ_c $ semileptonic decays

Authors:Sheng-Qi Zhang, Cong-Feng Qiao

Abstract: Motivated by the recent experimental progress in the $ \Lambda_c $ decay that contains a neutron in the final state, we analyze the semileptonic decay $ \Lambda_c \rightarrow n \ell \nu_\ell $ in the framework of QCD sum rules. The transition form factors are analytically computed using three-point correlation functions and the Cutkosky cutting rules, which can be extrapolated into the physical region by employing the dipole parametrization. The branching fractions of $ \Lambda_c \rightarrow n e^+ \nu_e $ and $ \Lambda_c \rightarrow n \mu^+ \nu_{\mu} $ are estimated to be $ (0.280\pm 0.031)\%$ and $ (0.274\pm 0.030)\% $, respectively. Furthermore, we calculate as well the relevant decay asymmetry observables sensitive to new physics beyond the standard model. The numerical results of semileptonic decays $ \Lambda_c \rightarrow \Lambda \ell \nu_\ell $ are also given and confronted to the latest experimental data.

3.$B^{*}_c$ meson parameters and radiative decay width within the covariant confined quark model

Authors:Aidos Issadykov, Sayabek K. Sakhiyev

Abstract: In this work we tried to predict the parameters of $B^{*}_c$ meson. Simple assumptions gave us following parametres $m_{B_{c}^{*}}=6329\pm 10$ MeV and $f_{B_{c}^{*}}= 535.5\pm57.8$ MeV (for $\Lambda_{B_{c}^{*}}=2.26\pm 0.14$ GeV in covariant confined quark model). We calculated widths of radiative decays of $B^*_{q}$ mesons, where $q=u/d,s,c$ and compared them with other theoretical works. It was shown that the width of the $B_{c}^{*}$ meson very sensitive to the mass $m_{B_{c}^{*}}$ as expected and less to the size parameter $\Lambda_{B_{c}^{*}}$.

4.Magnetic and quadrupole moments of the $Z_{c}(4020)^+$, $Z_{c}(4050)^+$ and $Z_{c}(4600)^{+}$ states in the diquark-antidiquark picture

Authors:U. Ozdem

Abstract: The magnetic and quadrupole moments of the $Z_{c}(4020)^+$, $Z_{c}(4050)^+$ and $Z_{c}(4600)^{+}$ states are calculated within the QCD light-cone sum rules. To extract the magnetic and quadrupole moments of these states the compact diquark-antidiquark interpolating currents and distribution amplitudes of the on-shell photon are employed. The magnetic moments are acquired as $\mu_{Z_{c}} = 0.55 ^{+0.23}_{-0.22}~\mu_N$, $\mu_{Z^{1}_{c}}=1.11 ^{+0.27}_{-0.29}~\mu_N$, $\mu_{Z^2_{c}}=2.44 ^{+0.53}_{-0.48}~\mu_N$ for the $Z_{c}(4020)^+$, $Z_{c}(4050)^+$ and $Z_{c}(4600)^{+}$ states, respectively. We see that the magnetic moment results evaluated for the $Z_{c}4020)^+$, $Z_{c}(4050)^+$ and $Z_{c}(4600)^{+}$ states are large enough to be measured experimentally. We get a nonzero however small value for the quadrupole moments of $Z_c$ states indicating a nonspherical charge distribution. The comparison of any future experimental data on the magnetic and quadrupole moments of the $Z_{c}(4020)^+$, $Z_{c}(4050)^+$ and $Z_{c}(4600)^{+}$ states together with the results of the present study can shed light on the nature and inner structure of these states.

5.The strong vertices of bottom mesons $B$, $B^{*}$ and bottomonia $Υ$, $η_{b}$

Authors:Jie Lu, Guo-Liang Yu, Zhi-Gang Wang, Bin Wu

Abstract: In this article, the strong coupling constants of vertices $BB\Upsilon$, $BB^{*}\Upsilon$, $B^{*}B^{*}\Upsilon$, $BB^{*}\eta_{b}$ and $B^{*}B^{*}\eta_{b}$ are analyzed in the framework of QCD sum rules. In this work, all possible off-shell cases and the contributions of vacuum condensate terms including $\langle\overline{q}q\rangle$, $\langle\overline{q}g_{s}\sigma Gq\rangle$, $\langle g_{s}^{2}G^{2}\rangle$, $\langle f^{3}G^{3}\rangle$ and $\langle\overline{q}q\rangle\langle g_{s}^{2}G^{2}\rangle$ are considered. The momentum dependent strong coupling constants are first calculated and then are fitted into analytical functions $g(Q^{2})$ which are used to extrapolate into time-like regions to obtain the final values of strong coupling constants. The final results are $g_{BB\Upsilon}=40.67^{+7.55}_{-4.20}$, $g_{BB^{*}\Upsilon}=11.58^{+2.19}_{-1.09}$ GeV$^{-1}$, $g_{B^{*}B^{*}\Upsilon}=57.02^{+5.32}_{-5.31}$, $g_{BB^{*}\eta_{b}}=23.39^{+4.74}_{-2.30}$ and $g_{B^{*}B^{*}\eta_{b}}=12.49^{+2.12}_{-1.35}$ GeV$^{-1}$. These strong coupling constants are important input parameters which reflect the dynamic properties of the interactions among the mesons and quarkonia.

6.Measuring the Sterile Neutrino Mass in Spallation Source and Direct Detection Experiments

Authors:David Alonso-González, Dorian W. P. Amaral, Adriana Bariego-Quintana, David Cerdeno, Martín de los Rios

Abstract: We explore the complementarity of direct detection (DD) and spallation source (SS) experiments for the study of sterile neutrino physics. We focus on the sterile baryonic neutrino model: an extension of the Standard Model that introduces a massive sterile neutrino with couplings to the quark sector via a new gauge boson. In this scenario, the inelastic scattering of an active neutrino with the target material in both DD and SS experiments gives rise to a characteristic nuclear recoil energy spectrum that can allow for the reconstruction of the neutrino mass in the event of a positive detection. We first derive new bounds on this model based on the data from the COHERENT collaboration on CsI and LAr targets, which we find do not yet probe new areas of the parameter space. We then assess how well future SS experiments will be able to measure the sterile neutrino mass and mixings, showing that masses in the range 15-50 MeV can be reconstructed. We show that there is a degeneracy in the measurement of the sterile neutrino mixing that substantially affects the reconstruction of parameters for masses of the order of 40 MeV. Thanks to their lower energy threshold and sensitivity to the solar tau neutrino flux, DD experiments allow us to partially lift the degeneracy in the sterile neutrino mixings and considerably improve its mass reconstruction down to 9 MeV. Our results demonstrate the excellent complementarity between DD and SS experiments in measuring the sterile neutrino mass and highlight the power of DD experiments in searching for new physics in the neutrino sector.

7.Decorrelation using Optimal Transport

Authors:Malte Algren, John Andrew Raine, Tobias Golling

Abstract: Being able to decorrelate a feature space from protected attributes is an area of active research and study in ethics, fairness, and also natural sciences. We introduce a novel decorrelation method using Convex Neural Optimal Transport Solvers (Cnots), that is able to decorrelate continuous feature space against protected attributes with optimal transport. We demonstrate how well it performs in the context of jet classification in high energy physics, where classifier scores are desired to be decorrelated from the mass of a jet. The decorrelation achieved in binary classification approaches the levels achieved by the state-of-the-art using conditional normalising flows. When moving to multiclass outputs the optimal transport approach performs significantly better than the state-of-the-art, suggesting substantial gains at decorrelating multidimensional feature spaces.

8.Pulsar kicks in ultralight dark matter background induced by neutrino oscillation

Authors:Geatano Lambiase, Tanmay Kumar Poddar

Abstract: The interaction of neutrinos with ultralight scalar and vector dark matter backgrounds induce a modification of the neutrino dispersion relation. The effects of this modification are reviewed in the framework of asymmetric emission of neutrinos from the supernova core, and, in turn, of pulsar kicks. We consider the neutrino oscillations, focusing in particular to active-sterile conversion. The ultralight dark matter induced neutrino dispersion relation contains a term of the form $\delta {\bf \Omega}\cdot \hat{{\bf{p}}}$, where $\delta {\bf \Omega}$ is related to the ultralight dark matter field and $\hat{{\bf p}}$ is the unit vector along the direction of neutrino momentum. The relative orientation of ${\bf p}$ with respect to $\delta {\bf \Omega}$ affects the mechanism for the generation of the observed pulsar velocities. We obtain the resonance condition for the active-sterile neutrino oscillation in ultralight dark matter background and calculate the star parameters in the resonance surface so that both ultralight scalar and vector dark matter backgrounds can explain the observed pulsar kicks. The asymmetric emission of neutrinos in presence of ultralight dark matter background results gravitational memory signal which can be probed from the gravitational wave detectors. We also establish a connection between the ultralight dark matter parameters and the standard model extension parameter.

9.Single Transverse Spin Asymmetry as a New Probe of SMEFT Dipole Operators

Authors:Xin-Kai Wen, Bin Yan, Zhite Yu, C. -P. Yuan

Abstract: Electroweak dipole operators in the Standard Model Effective Field Theory (SMEFT) are important indirect probes of quantum effects of new physics beyond the Standard Model (SM), yet they remain poorly constrained by current experimental analyses for lack of interference with the SM amplitudes in constructing cross section observables. In this Letter, we point out that dipole operators flip fermion helicities so are ideally studied through single transverse spin asymmetries. We illustrate this at a future electron-positron collider with transversely polarized beams, where such effect exhibits as azimuthal $\cos\phi$ and $\sin\phi$ distributions which originate from the interference of the electron dipole operators with the SM and are linearly dependent on their Wilson coefficients. This new method can improve the current constraints on the electron dipole couplings by one to two orders of magnitude, without depending on other new physics operators, and can also simultaneously constrain both their real and imaginary parts, offering a new opportunity for probing potential $CP$-violating effects.

10.Heavy-flavor hadronization mechanism from pp to AA collisions: a theoretical perspective

Authors:Andrea Beraudo

Abstract: The interest in studying heavy-flavor hadronization in high-energy nuclear collisions is twofold. On one hand hadronization represents a source of systematic uncertainties in phenomenological attempts of extracting heavy-flavor transport coefficients in the Quark Gluon Plasma which one assumes to be produced in the collision. Hence, developing the most possible reliable model for this process is important to get a precise and accurate estimate of a fundamental property of hot QCD. On the other hand studying how hadronization changes in the presence of a dense medium of colored partons can be considered an issue of interest by itself. In particular, the observation of modifications of heavy-flavor hadronization in proton-proton collisions strongly suggests that also in this case a small droplet of Quark-Gluon Plasma can be formed. Here we try to provide a general overview on heavy-flavor hadronization, from pp to AA collisions, stressing the aspects and challenges common to all mechanisms proposed in the literature. Then, focusing on a particular model, we show how a consistent description of several observables involving heavy-flavor hadrons can be obtained

11.Correlating the CDF $W$-mass shift with the muon $g-2$ and the $b \to s \ell^+ \ell^-$ transitions

Authors:Xin-Qiang Li, Ze-Jun Xie, Ya-Dong Yang, Xing-Bo Yuan

Abstract: Motivated by the latest CDF $W$-mass measurement as well as the muon $g-2$ anomaly and the discrepancies observed in $b \to s \ell^+ \ell^-$ transitions, we propose an extension of the Standard Model (SM) with the $SU(2)_L$-singlet vector-like fermion partners that are featured by additional $U(1)^\prime$ gauge symmetry. The fermion partners have the same SM quantum numbers as of the right-handed SM fermions, and can therefore mix with the latter after the electroweak and the $U(1)^\prime$ symmetry breaking. As a result, desirable loop-level corrections to the $(g-2)_\mu$, the $W$-boson mass $m_W$ and the Wilson coefficient $C_9$ in $b \to s \mu^+ \mu^-$ transitions can be obtained. The final allowed parameter space is also consistent with the constraints from the $Z \to \mu^+ \mu^-$ decay, the neutrino trident production and the LHC direct searches for the vector-like quarks and leptons.

12.Recent results from the CMS Proton Precision Spectrometer

Authors:C. Royon

Abstract: The Precision Proton Spectrometer (PPS) is a new subdetector of CMS that provides a powerful tool for the advancement of beyond standard model searches. We present recent results obtained with the PPS subdetector illustrating the unique sensitivity achieved using proton tagging.

13.Jet separated by a large rapidity gap at the Tevatron and the LHC

Authors:C. Royon

Abstract: We compare the recent measurements of gap between jets at the Tevatron and the LHC with the Balitski Fadin Kuraev Lipatov framework. While a good agreement is obtained with Tevatron data, some discrepancies especially for the rapidity separation between jets are found that can be explained by an excess of initial state radiation in PYTHIA.

14.Scalar NSI: A unique tool for constraining absolute neutrino masses via $ν$-oscillations

Authors:Abinash Medhi, Arnab Sarker, Moon Moon Devi

Abstract: In the standard interaction scenario, a direct measurement of absolute neutrino masses via neutrino oscillations is not feasible, as the oscillations depend only on the mass-squared differences. However, the presence of scalar non-standard interactions can introduce sub-dominant terms in the oscillation Hamiltonian that can directly affect the neutrino mass matrix and thereby making scalar NSI a unique tool for neutrino mass measurements. In this work, for the first time, we constrain the absolute masses of neutrinos by probing scalar NSI. We show that a bound on the lightest neutrino mass can be induced in the presence of scalar NSI at DUNE. We find that the lightest neutrino mass can be best constrained with $\eta_{\tau\tau}$ and $\eta_{\mu\mu}$ at $2\sigma$ C.L. for normal and inverted hierarchy respectively. This study suggests that scalar NSI can serve as an interesting avenue to constrain the absolute neutrino masses in long-baseline neutrino experiments via neutrino oscillations.

15.$B^+$ decay to $K^+ηη$ with ($ηη$) from the $D\bar{D}(3720)$ bound state

Authors:Pedro C. S. Brandão, Jing Song, Luciano M. Abreu, E. Oset

Abstract: We search for a $B$ decay mode where one can find a peak for a $D \bar{D}$ bound state predicted in effective theories and in Lattice QCD calculations, which has also been claimed from some reactions that show an accumulated strength in $D \bar{D}$ production at threshold. We find a good candidate in the $B^+\to K^+ \eta\eta$ reaction, by looking at the $\eta\eta$ mass distribution. The reaction proceeds via a first step in which one has the $B^+\to D_s^{*+} \bar{D}^0$ reaction followed by $D_s^{*+}$ decay to $D^0 K^+$ and a posterior fusion of $D^0 \bar{D}^0$ to $\eta \eta$, implemented trough a triangle diagram that allows the $D^0 \bar{D}^0$ to be virtual and produce the bound state. The choice of $\eta\eta$ to see the peak is based on results of calculations that find the $\eta\eta$ among the light pseudoscalar channels with stronger coupling to the $D \bar{D}$ bound state. We find a neat peak around the predicted mass of that state in the $\eta\eta$ mass distribution, with an integrated branching ratio for $B^+\to K^+$ ($D\bar{D}$, bound) ; ($D\bar{D}$, bound) $\to \eta \eta$ of the order of $1.5 \times 10^{-4}$, a large number for hadronic $B$ decays, which should motivate its experimental search.

16.Solving the strong CP problem by a $\barθ$-characterized mirror symmetry

Authors:Pei-Hong Gu

Abstract: In the standard model QCD Lagrangian, a term of CP violating gluon density is theoretically expected to have a physical coefficient $\bar{\theta}$ of the order of unity. However, the upper bound on the electric dipole moment of neutron enforces the value of $\bar{\theta}$ to be extremely small. Such a huge gap between theoretical expectation and experimental result is commonly known as the strong CP problem. To solve this puzzle in an appealing context of two Higgs doublets, we propose an economical $\bar{\theta}$-characterized mirror symmetry between two Higgs singlets with respective discrete symmetries. In our scenario, the parameter $\bar{\theta}$ can completely disappear from the full Lagrangian after the standard model fermions take a proper phase rotation as well as the Higgs doublets and singlets. Moreover, all of new physics for solving the strong CP problem can be allowed near the TeV scale.

17.Axions and Cosmic Magnetic Fields

Authors:George B. Field, Sean M. Carroll

Abstract: We argue that if axions are the dark matter, their coupling to electromagnetism results in exponential growth of a helical magnetic field when the axion field first rolls down its potential. After an inverse cascade, the relevant length scales to day are of order 10-100 kpc, of astrophysical interest. Our mechanism for allowing the field to grow relies on a nuance of MHD. Faraday's Law says that an electric field is needed to create a magnetic field. Previous authors relied on conventional Ohm's law to calculate E, but the resistivity is negligible and therefore they assume E is as well. We use a modified Ohm's Law that includes the effects of self-induction in limiting the current driven by a given E, which allows a magnetic field to grow.

18.Bulk-to-boundary propagators with arbitrary spin J in soft-wall AdS/QCD

Authors:Valery E. Lyubovitskij, Ivan Schmidt

Abstract: We derive the equations of motion for the bulk-to-boundary propagators of the AdS boson and fermion fields with arbitrary spin J in a soft-wall AdS/QCD model and solve it analytically. It provides the opportunity to study transition form factors induced by these bulk-to-boundary propagators, both for on-shell and off-shell hadrons. This is a continuation of our study of hadron form factors induced by the bulk-to-boundary propagator with spin J=1 (e.g., electromagnetic form factors of mesons, nucleons, and nucleon resonances).

1.Diffusion and fluctuations of open charmed hadrons in an interacting hadronic medium

Authors:Kangkan Goswami, Kshitish Kumar Pradhan, Dushmanta Sahu, Raghunath Sahoo

Abstract: Heavy quarks are excellent probes to understand the hot and dense medium formed in ultra-relativistic collisions. In a hadronic medium, studying the transport properties, e.g. the drag ($\gamma$), momentum diffusion ($B_{0}$), and spatial diffusion ($D_{s}$) coefficients of open charmed hadrons can provide useful information about the medium. Moreover, the fluctuations of charmed hadrons can help us to locate the onset of their deconfinement. In this work, we incorporate attractive and repulsive interactions in the well-established van der Waals hadron resonance gas model (VDWHRG) and study the diffusion and fluctuations of charmed hadrons. This study helps us understand the importance of interactions in the system, which significantly affect both the diffusion and fluctuations of charmed hadrons.

2.$φ(2170)$ decaying to $φππ$ and $φK\bar{K}$

Authors:Yun-Hua Chen

Abstract: Within the framework of dispersion theory, we study the the processes $e^+e^-\to \phi(2170) \to \phi \pi\pi(K\bar{K})$. The strong pion-pion final-state interactions, especially the $K\bar{K}$ coupled channel in the $S$-wave, are taken into account in a model-independent way using the Omn\`es function solution. Through fitting the experimental data of the $\pi\pi$ and $\phi\pi$ invariant mass distributions of the $e^+e^- \to \phi(2170) \to \phi \pi^+\pi^-$ process, the low-energy constants in the chiral Lagrangian are determined. The theoretical prediction for the cross sections ratio ${\sigma(e^+e^- \to \phi(2170)\to \phi K^+ K^-)}/{\sigma(e^+e^- \to \phi(2170)\to \phi\pi^+\pi^-)}$ is given, which could be useful for selecting the physical solution when the fit to the $e^+e^- \to \phi K^+ K^-$ cross section distribution is available in the future. Our results suggest that above the kinematical threshold of $\phi K\bar{K}$, the mechanism $e^+e^- \to \phi K^+ K^-$ with the kaons rescattering to a pion pair plays an important role in the $e^+e^- \to \phi\pi^+\pi^-$ transition.

3.Full event simulation of Photoproduction at NLO QCD in Sherpa

Authors:Peter Meinzinger

Abstract: Photoproduction is an important mode for the production of jets and electro-weak particles at lepton--lepton and lepton--hadron colliders and allows for interesting studies of exclusive production at hadron--hadron colliders. In this talk, I will review recent efforts of extending the Sherpa event generator to include the calculation of photoproduction cross sections for electron and proton beams, including the simulation of underlying events. The framework is validated using data of jet production at the HERA and LEP experiments and lepton production at the LHC. I will discuss advances towards achieving matched NLO accuracy and fully capturing the dynamics of inclusive and exclusive photoproduction at different colliders.

4.Toward a generative modeling analysis of CLAS exclusive $2π$ photoproduction

Authors:T. Alghamdi, Y. Alanazi, M. Battaglieri, L. Bibrzycki, A. V. Golda, A. N. Hiller Blin, E. L. Isupov, Y. Li, L. Marsicano, W. Melnitchouk, V. I. Mokeev, G. Montana, A. Pilloni, N. Sato, A. P. Szczepaniak, T. Vittorini

Abstract: AI-supported algorithms, particularly generative models, have been successfully used in a variety of different contexts. In this work, we demonstrate for the first time that generative adversarial networks (GANs) can be used in high-energy experimental physics to unfold detector effects from multi-particle final states, while preserving correlations between kinematic variables in multidimensional phase space. We perform a full closure test on two-pion photoproduction pseudodata generated with a realistic model in the kinematics of the Jefferson Lab CLAS g11 experiment. The overlap of different reaction mechanisms leading to the same final state associated with the CLAS detector's nontrivial effects represents an ideal test case for AI-supported analysis. Uncertainty quantification performed via bootstrap provides an estimate of the systematic uncertainty associated with the procedure. The test demonstrates that GANs can reproduce highly correlated multidifferential cross sections even in the presence of detector-induced distortions in the training datasets, and provides a solid basis for applying the framework to real experimental data.

5.Distinguishing between Dirac and Majorana neutrinos using temporal correlations

Authors:Bhavya Soni, Sheeba Shafaq, Poonam Mehta

Abstract: In the context of two flavour neutrino oscillations, it is understood that the $2\times 2$ mixing matrix is parameterized by one angle and a Majorana phase. However, this phase does not impact the oscillation probabilities in vacuum or in matter with constant density. Interestingly, the Majorana phase becomes relevant when we describe neutrino oscillations along with neutrino decay. This is due to the fact that effective Hamiltonian has Hermitian and anti-Hermitian components which cannot be simultaneously diagonalized (resulting in decay eigenstates being different from the mass eigenstates). We consider the $\cal PT$ symmetric non-Hermitian Hamiltonian describing two flavour neutrino case and study the violation of Leggett-Garg Inequalities (LGI) in this context for the first time. We demonstrate that temporal correlations in the form of LGI allow us to probe whether neutrinos are Dirac or Majorana. We elucidate the role played by the mixing and decay parameters on the extent of violation of LGI. We emphasize that for optimized choice of parameters, the difference in $K_4$ ($K_3$) for Dirac and Majorana case is $\sim 15\%$ ($\sim 10\%$).

6.Exploring Non-Standard Quark Interactions through Solar Neutrino Studies

Authors:Ilídio Lopes

Abstract: We investigate the effects of a Non-Standard Interaction (NSI) extension of the standard model of particle physics on solar neutrino flavour oscillations. This NSI model introduces a $U_{Z^\prime}(1)$ gauge symmetry through a $Z^\prime$ boson that mixes with the photon, creating a neutral current between active neutrinos and matter fields via a unique coupling to up and down quarks. The interaction is defined by a single parameter, $\zeta_o$, which is related to the $Z^\prime$ boson's mass $m_{Z^\prime}$ and coupling constant $g_{Z^\prime}$. Notably, this model relaxes the bounds on Coherent Elastic Neutrino-Nucleus Scattering experiments and fits the experimental values of the anomalous magnetic dipole moment of the muon. In this study, we use solar neutrino measurements and an up-to-date standard solar model to evaluate the neutrino flavour oscillations and assess the constraints on $\zeta_o$. Our study indicates that the NSI model aligns with the current solar neutrino data when $\zeta_o$ is between $-0.7$ and $0.002$. These models have $\chi^2_{\nu}$ values equal to or better than the standard neutrino flavor oscillation model, which stands at a $\chi^2_{\nu}$ of 3.12. The best NSI model comes with a $\zeta_o$ value of -0.2 and a $\chi^2_{\nu}$ of 2.96. Including extra data from the Darwin experiment in our analysis refines the range of $\zeta_o$ values from $-0.7$ to $0.002$, down to $-0.5$ to $-0.002$. These results hint at the possible existence of novel interactions, given that NSI models achieve a comparable or superior fit to the solar neutrino data when contrasted with the prevailing standard model of neutrino flavour oscillation.

7.NANOGrav spectral index $γ=3$ from melting domain walls

Authors:E. Babichev, D. Gorbunov, S. Ramazanov, R. Samanta, A. Vikman

Abstract: We discuss cosmic domain walls described by a tension red-shifting with the expansion of the Universe. These melting domain walls emit gravitational waves (GW) with the low-frequency spectral shape $\Omega_{gw}\propto f^{2}$ corresponding to the spectral index $\gamma=3$ favoured by the recent NANOGrav 15 yrs data. We discuss a concrete high-energy physics scenario proposed in Refs. [1,2] which leads to such a melting domain wall network in the early Universe. This scenario involves a feebly coupled scalar field $\chi$, which can serve as a promising dark matter candidate. We identify parameters of the model matching the GW characteristics observed in the NANOGrav data. The dark matter mass is pushed to the ultra-light range below $10^{-11}-10^{-12}\,\text{eV}$ which is accessible through planned observations thanks to the effects of superradiance of rotating black holes.

8.Singling out SO(10) GUT models using recent PTA results

Authors:Stefan Antusch, Kevin Hinze, Shaikh Saad, Jonathan Steiner

Abstract: In this work, we construct promising model building routes towards SO(10) GUT inflation and examine their ability to explain the recent PTA results hinting at a stochastic gravitational wave (GW) background at nanohertz frequencies. We consider a supersymmetric framework within which the so-called doublet-triplet splitting problem is solved without introducing fine-tuning. Additionally, realistic fermion masses and mixings, gauge coupling unification, and cosmic inflation are incorporated by utilizing superfields with representations no higher than the adjoint representation. Among the three possible scenarios, two of these cases require a single adjoint Higgs field, and do not lead to cosmic strings. In contrast, the third scenario featuring two adjoints, can lead to a network of metastable cosmic strings that generates a GW background contribution compatible with the recent PTA findings and testable by various ongoing and upcoming GW observatories.

9.Properties of the $η_q$ leading-twist distribution amplitude and its effects to the $B/D^+ \toη^{(\prime)}\ell^+ ν_\ell$ decays

Authors:Dan-Dan Hu, Xing-Gang Wu, Hai-Bing Fu, Tao Zhong, Zai-Hui Wu, Long Zeng

Abstract: The $\eta^{(\prime)}$-mesons in the quark-flavor basis are mixtures of two mesonic states $|\eta_{q}\rangle=|\bar u u+\bar d d\rangle/\sqrt 2$ and $|\eta_{s}\rangle=|\bar s s\rangle$. In the previous work, we have made a detailed study on the $\eta_{s}$ leading-twist distribution amplitude. As a sequential work, in the present paper, we fix the $\eta_q$ leading-twist distribution amplitude by using the light-cone harmonic oscillator model for its wave function and by using the QCD sum rules within the QCD background field to calculate its moments. The input parameters of $\eta_q$ leading-twist distribution amplitude $\phi_{2;\eta_q}$ at an initial scale $\mu_0\sim 1$ GeV are then fixed by using those moments. The sum rules for the $0_{\rm th}$-order moment can also be used to fix the magnitude of $\eta_q$ decay constant, which gives $f_{\eta_q}=0.141\pm0.005$ GeV. As an application of the present derived $\phi_{2;\eta_q}$, we calculate the transition form factors $B(D)^+ \to\eta^{(\prime)}$ by using the QCD light-cone sum rules up to twist-4 accuracy and by including the next-to-leading order QCD corrections to the twist-2 part, and then fix the related CKM matrix element and the decay width for the semi-leptonic decays $B(D)^+ \to\eta^{(\prime)}\ell^+ \nu_\ell$.

10.Baryogenesis and Dark Matter in the Mirror Twin Higgs

Authors:Pedro Bittar, Gustavo Burdman, Larissa Kiriliuk

Abstract: We consider a natural asymmetric dark matter (ADM) model in the mirror twin Higgs (MTH). We show that it is possible to obtain the correct dark matter (DM) abundance when a twin baryon is the DM without the need of explicit breaking of the MTH $\mathbb{Z}_2$ symmetry in the dimensionless couplings (i.e. without hard $\mathbb{Z}_2$ breaking). We illustrate how this is possible in a specific baryogenesis setup, which also leads to ADM. In the simplest scenario we obtain $m_{\rm DM}\sim O(1)$~GeV, just above the proton mass. We show estimates for direct detection rates at present and future experiments.

11.The Mikheyev-Smirnov-Wolfenstein Matter Potential at the One-loop Level in the Standard Model

Authors:Jihong Huang, Shun Zhou

Abstract: When neutrinos are propagating in ordinary matter, their coherent forward scattering off background particles results in the so-called Mikheyev-Smirnov-Wolfenstein (MSW) matter potential, which plays an important role in neutrino flavor conversions. In this paper, we present a complete one-loop calculation of the MSW matter potential in the Standard Model (SM). First, we carry out the one-loop renormalization of the SM in the on-shell scheme, where the electromagnetic fine-structure constant $\alpha$, the weak gauge-boson masses $m^{}_W$ and $m^{}_Z$, the Higgs-boson mass $m^{}_h$ and the fermion masses $m^{}_f$ are chosen as input parameters. Then, the finite corrections to the scattering amplitudes of neutrinos with the electrons and quarks are calculated, and the one-loop MSW matter potentials are derived. Adopting the latest values of all physical parameters, we find that the relative size of one-loop correction to the charged-current matter potential of electron-type neutrinos or antineutrinos turns out to be $6\%$, whereas that to the neutral-current matter potential of all-flavor neutrinos or antineutrinos can be as large as $8\%$. The implications of such corrections for neutrino oscillations are briefly discussed.

12.Metastable cosmic strings

Authors:Wilfried Buchmuller, Valerie Domcke, Kai Schmitz

Abstract: Many symmetry breaking patterns in grand unified theories (GUTs) give rise to cosmic strings that eventually decay when pairs of GUT monopoles spontaneously nucleate along the string cores. These strings are known as metastable cosmic strings and have intriguing implications for particle physics and cosmology. In this article, we discuss the current status of metastable cosmic strings, with a focus on possible GUT embeddings and connections to inflation, neutrinos, and gravitational waves (GWs). The GW signal emitted by a network of metastable cosmic strings in the early universe differs, in particular, from the signal emitted by topologically stable strings by a suppression at low frequencies. Therefore, if the underlying symmetry breaking scale is close to the GUT scale, the resulting GW spectrum can be accessible at current ground-based interferometers as well as at future space-based interferometers, such as LISA, and at the same time account for the signal in the most recent pulsar timing data sets. Metastable cosmic strings thus nourish the hope that future GW observations might shed light on fundamental physics close to the GUT scale.

13.Supercooling in Radiative Symmetry Breaking: Theory Extensions, Gravitational Wave Detection and Primordial Black Holes

Authors:Alberto Salvio

Abstract: First-order phase transitions, which take place when the symmetries are predominantly broken (and masses are then generated) through radiative corrections, produce observable gravitational waves and primordial black holes. We provide a model-independent approach that is valid for large-enough supercooling to quantitatively describe these phenomena in terms of few parameters, which are computable once the model is specified. The validity of a previously-proposed approach of this sort is extended here to a larger class of theories. Among other things, we identify regions of the parameter space that correspond to the background of gravitational waves recently detected by pulsar timing arrays (NANOGrav, CPTA, EPTA, PPTA) and others that are either excluded by the observing runs of LIGO and Virgo or within the reach of future gravitational wave detectors. Furthermore, we find regions of the parameter space where primordial black holes produced by large over-densities due to such phase transitions can account for dark matter. Finally, it is shown how this model-independent approach can be applied to specific cases, including a phenomenological completion of the Standard Model with right-handed neutrinos and gauged $B-L$ undergoing radiative symmetry breaking.

14.Remarks on the Axion Domain Wall Problem

Authors:Michael Dine

Abstract: Theories in which the Peccei-Quinn phase transition occurs after inflation tend to suffer from problematic domain walls. One possible solution involves a small, explicit breaking ot the symmetry. But this raises other potential issues. We review some aspects of axion domain walls, focussing especially on this proposed solution. We argue, in disagreement with some recent literature, that there is little axion radiation from the system until the domains actually collapse. The same applies to gravitational waves and electromagnetic radiation. The final stages of the collapse yields small numbers of extremely energetic axions, which interact only rarely with ordinary matter, and are thus relatively harmless. We then note that, if one accepts a remarkable coincidence, this solution can be acceptable. We consider a possible explanation of the required coincidence

15.Sphaleron in the Higgs Triplet Model

Authors:Jiahang Hu, Bingrong Yu, Shun Zhou

Abstract: The Higgs triplet model (HTM) extends the Standard Model (SM) by one complex triplet scalar (also known as the type-II seesaw model), offering a simple and viable way to account for nonzero neutrino masses. On the other hand, the nontrivial couplings of the triplet to the gauge fields and to the SM Higgs field are expected to influence the topological vacuum structure of the SM, and consequently, the energy and the field configuration of the electroweak sphaleron. The sphaleron process plays a crucial role in dynamically generating the baryon asymmetry of the Universe. In this work, we study the vacuum structure of the gauge and Higgs fields and calculate the saddle-point sphaleron configuration in the HTM. The coupled nonlinear equations of motion of the sphaleron are solved using the spectral method. We find the inclusion of the triplet scalar could in principle significantly change the sphaleron energy compared with the SM. Nevertheless, at zero temperature, the current stringent experimental constraint on the vacuum expectation value of the triplet suppresses the difference. Interestingly, we find that there still exists some narrow parameter space where the sphaleron energy can be enhanced up to $30\%$ compared with the SM case.

16.Quark/Gluon Discrimination and Top Tagging with Dual Attention Transformer

Authors:Minxuan He, Daohan Wang

Abstract: Jet tagging is a crucial classification task in high energy physics. Recently the performance of jet tagging has been significantly improved by the application of deep learning techniques. In this work, we propose Particle Dual Attention Transformer for jet tagging, a new transformer architecture which captures both global information and local information simultaneously. Based on the point cloud representation, we introduce the Channel Attention module to the point cloud transformer and incorporates both the pairwise particle interactions and the pairwise jet feature interactions in the attention mechanism. We demonstrate the effectiveness of the P-DAT architecture in classic top tagging and quark-gluon discrimination tasks, achieving competitive performance compared to other benchmark strategies.

1.Triangle singularity in the $J/ψ\to γ\bar{p} Δ$ decay

Authors:Ke Wang, Rong Li, Bo-Chao Liu

Abstract: In this work, we study the role of triangle singularity in the $J/\psi \to \gamma \bar{p} \Delta$ decay. We find that through a triangle mechanism, involving a triangle loop composed by $\omega$, $\pi$ and $p$, this decay may develop a triangle singularity and produce a visible peak in the invariant mass $M_{\gamma\Delta}$ around 1.73 GeV with a width of 0.02 GeV. Such a triangle mechanism may also cause significant spin effects on the final $\Delta$, which can be detected by measuring its spin density matrix elements. Our calculations show that the branching ratios due to the triangle mechanism is Br($J/\psi\to \gamma \bar p\Delta,\Delta\to \pi p$)=$1.058\times 10^{-6}$. Hopefully, this reaction can be investigated at BESIII and future experiments, e.g. Super Tau-Charm Facility, and the narrow width of the induced structure, the moving TS position and the distinct features of the spin density matrix elements of the $\Delta$ may serve as signals for the triangle singularity mechanism.

2.Modular flavor symmetric models

Authors:Tatsuo Kobayashi, Morimitsu Tanimoto

Abstract: We review the modular flavor symmetric models of quarks and leptons focusing on our works. We present some flavor models of quarks and leptons by using finite modular groups and discuss the phenomenological implications. The modular flavor symmetry gives interesting phenomena at the fixed point of modulus. As a representative, we show the successful texture structure at the fixed point $\tau = \omega$. We also study CP violation, which occurs through the modulus stabilization. Finally, we study SMEFT with modular flavor symmetry by including higher dimensional operators.

3.Exploration of possible signals beyond special relativity using high-energy astroparticle physics

Authors:Maykoll A. Reyes

Abstract: To unify the standard model of particle physics and general relativity, we may require a quantum description of gravity, which will change our notion of spacetime at very high energies. In this dissertation we explore possible traces of new physics beyond special relativity, using the propagation of high energy astroparticles. For this purpose, the two ways of going beyond Lorentz invariance are presented, a breaking of the Lorentz invariance (Lorentz invariance violation or LIV or its deformation (doubly special relativity or DSR), emphasizing their conceptual and phenomenological differences. For the study of LIV, the work focuses on the prediction of modifications in the expected neutrino flux on Earth, both from astrophysical and cosmogenic origin (from the interaction of cosmic rays with the background radiation during their propagation). For the study of DSR we focus instead on the search for anomalies in the time of flight of massless particles (time delays) and on the study of the expected flux of gamma rays on Earth. The results obtained show the possibility of using astroparticle observations as a window to quantum gravity phenomenology, at energies attainable at present and/or in the very near future.

4.Estimates of absolute branching fractions for the $f_0(1710)$ decays and radiative transitions $ψ(2S)\toγf_0(1710)$ and $Υ(1S)\toγf_0(1710)$

Authors:N. N. Achasov, G. N. Shestakov

Abstract: Using the result of the VES Collaboration for $Br(J/\psi\to\gamma f_0(1710))$, we estimate the absolute branching fractions for the $f_0(1710)$ decays into $\pi\pi$, $K\bar K$, $\eta\eta$, $\eta\eta' $, $\omega\omega$, and $\omega\phi$. In addition, we estimate $Br(\psi(2S)\to\gamma f_0(1710))\approx3.5\times10^{-5}$ and $Br(\Upsilon(1S)\to\gamma f_0(1710))\approx1\times10^{-5}$.

5.New Early Dark Energy as a solution to the $H_0$ and $S_8$ tensions

Authors:Florian Niedermann, Martin S. Sloth

Abstract: New Early Dark Energy introduces a new phase of dark energy that decays in a fast-triggered phase transition around matter-radiation equality. The presence of a trigger mechanism sets it apart from other early dark energy models. Here, we will argue that New Early Dark Energy offers a simple and natural framework to extend $\Lambda$CDM while also providing a pathway to resolving the $H_0$ tension alongside its smaller cousin, the $S_8$ tension. At the microscopic level, we discuss the possibility that the trigger is either given by an ultralight scalar field or a dark sector temperature. In both cases, it prompts the transition of an $\mathrm{eV}$-mass scalar field from its false to its true minimum. Furthermore, we argue that the same phase transition could give rise to a dynamic process for generating neutrino masses.

6.Signatures of afterglows from light dark matter boosted by supernova neutrinos in current and future large underground detectors

Authors:Yen-Hsun Lin, Tsung-Han Tsai, Guey-Lin Lin, Henry Tsz-King Wong, Meng-Ru Wu

Abstract: Supernova neutrino boosted dark matter (SN$\nu$ BDM) and its afterglow effect have been shown to be a promising signature for beyond Standard Model (bSM) physics. The time-evolution feature of SN$\nu$ BDM allows for possibly direct inference of DM mass $m_\chi$, and results in significant background suppression with improving sensitivity. This paper extends the earlier study and provides a general framework for computing the SN$\nu$ BDM fluxes for a supernova that occurs at any location in our galaxy. A bSM $U(1)_{L_\mu-L_\tau}$ model with its gauge boson coupling to both DM and the second and third generation of leptons is considered, which allows for both DM-$\nu$ and DM-$e$ interactions. Detailed analysis of the temporal profile, angular distribution, and energy spectrum of the SN$\nu$ BDM are performed. Unique signatures in SN$\nu$ BDM allowing extraction of $m_\chi$ and detail features that contain information of the underlying interaction type are discussed. Expected sensitivities on the above new physics model from Super-Kamiokande, Hyper-Kamiokande, and DUNE detections of BDM events induced by the next galactic SN are derived and compared with the existing bounds.

7.Electron-positron, parton-parton and photon-photon production of $τ$-lepton pairs: anomalous magnetic and electric dipole moments spin effects

Authors:Sw. Banerjee, A. Yu. Korchin, E. Richter-Was, Z. Was

Abstract: Anomalous contributions to the electric and magnetic dipole moments of the $\tau$ lepton from new physics scenarios have brought renewed interest in the development of new charge-parity violating signatures in $\tau$ pair production at Belle II energies, and also at higher energies of the Large Hadron Collider and the Future Circular Collider. In this paper, we discuss the effects of spin correlations, including transverse degrees of freedom, in the $\tau$ pair production and decay. These studies include calculating analytical formulas, obtaining numerical results, and building semi-realistic observables sensitive to the transverse spin correlations induced by the dipole moments of the $\tau$ lepton. The effects of such anomalous contributions to the dipole moments are introduced on top of precision simulations of $e^-e^+ \to \tau^-\tau^+$, $q\bar{q} \to \tau^-\tau^+$ and $\gamma\gamma \to \tau^-\tau^+$ processes, involving multi-body final states. Respective extensions of the Standard Model amplitudes and the reweighting algorithms are implemented into the {\tt KKMC} Monte Carlo, which is used to simulate $\tau$ pair production in $e^-e^+$ collisions, and the {\tt TauSpinner} program, which is used to reweight events with $\tau$ pair produced in $pp$ collisions.

8.SN1987A and neutrino non-radiative decay

Authors:Pilar Iváñez-Ballesteros APC, Paris, M. Cristina Volpe APC, Paris

Abstract: We investigate neutrino non-radiative two-body decay in vacuum, in relation to SN1987A. In a full $3\nu$ decay framework, we perform a detailed likelihood analysis of the 24 neutrino events from SN1987A observed by Kamiokande-II, IMB, and Baksan. We consider both normal and inverted neutrino mass orderings, and the possibility of strongly hierarchical and quasi-degenerate neutrino mass patterns. The results of the likelihood analysis show that the sensitivity is too low to derive bounds in the case of normal mass ordering. On the contrary, in the case of inverted mass ordering we obtain the bound $\tau/m \ge 2.4 \times 10^{5}$ s/eV ($1.2 \times 10^{5}$) s/eV at 68 $\%$ (90 $\%$) CL on the lifetime-to-mass ratio of the mass eigenstates $\nu_2$ and $\nu_1$.

9.New physics analysis of $Λ_b\to (Λ^*(\to pK^-), Λ(\to pπ))(μ^{+}μ^{-},\,ν\barν)$ baryonic decays under SMEFT framework

Authors:Nilakshi Das, Rupak Dutta

Abstract: The di-leptons and di-neutrinos observed in the final states of flavor-changing neutral b decays provide an ideal platform for probing physics beyond the standard model. Although the latest measurements of $R_{K^{(*)}}$ agree well with the standard model prediction, there exists several other observables such as $P_5^{\prime}$, $\mathcal{B}(B_s\to \phi \mu^{+}\mu^{-})$ and $\mathcal{B}(B_s\to \mu^{+}\mu^{-})$ in $b\to s \ell\ell$ transition decays that shows deviation from the standard model prediction. Similalry, very recently Belle II collaboration reported a more precise upper bound of $\mathcal{B}(B\to K^+\nu\bar{\nu}) < 4.1\times 10^{-5}$ by employing a new inclusive tagging approach and it also deviates from the standard model expectation. The $b\to s l^{+}l^{-}$ and $b\to s\nu\bar{\nu}$ transition decays are related not only in the standard model but also in beyond the standard model physics due to $SU(2)_L$ gauge symmetry, and can be most effectively investigated using the standard model effective field theory formalism. Additionally, the $b\to s\nu\bar{\nu}$ decay channels are theoretically cleaner than the corresponding $b\to s l^{+}l^{-}$ decays, as these processes do not get contributions from non-factorizable corrections and photonic penguin contributions. In this context, we study $\Lambda_b\to (\Lambda^*(\to pK^-), \Lambda(\to p\pi))({\mu}^{+}\mu^{-},\,\nu\bar{\nu})$ baryonic decays undergoing $b\to s \ell^{+}\ell^{-}$ and $b\to s\nu\bar{\nu}$ quark level transitions in a standard model effective field theory formalism. We give predictions of several observables pertaining to these decay channels in the standard model and in case of several new physics scenarios.

10.Recent progress on in-medium properties of heavy mesons from finite-temperature EFTs

Authors:Gloria Montana, Angels Ramos, Laura Tolos, Juan M. Torres-Rincon

Abstract: Mesons with heavy flavor content are an exceptional probe of the hot QCD medium produced in heavy-ion collisions. In the past few years, significant progress has been made toward describing the modification of the properties of heavy mesons in the hadronic phase at finite temperature. Ground-state and excited-state thermal spectral properties can be computed within a self-consistent many-body approach that employs appropriate hadron-hadron effective interactions, providing a unique opportunity to confront hadronic Effective Field Theory predictions with recent and forthcoming lattice QCD simulations and experimental data. In this article, we revisit the application of the imaginary-time formalism to extend the calculation of unitarized scattering amplitudes from the vacuum to finite temperature. These methods allow us to obtain the ground-state thermal spectral functions. The thermal properties of the excited states that are dynamically generated within the molecular picture are also directly accessible. We present here the results of this approach for the open-charm and open-bottom sectors. We also analyze how the heavy-flavor transport properties, which are strongly correlated to experimental observables in heavy-ion collisions, are modified in hot matter. In particular, transport coefficients can be computed using an off-shell kinetic theory that is fully consistent with the effective theory describing the scattering processes. The results of this procedure for both charm and bottom transport coefficients are briefly discussed.

11.Low Scale Seesaw with Local Lepton Number

Authors:Hridoy Debnath, Pavel Fileviez Perez

Abstract: We discuss a class of theories for Majorana neutrinos where the total lepton number is a local gauge symmetry. These theories predict a dark matter candidate from anomaly cancellation. We discuss the properties of the dark matter candidate and using the cosmological bounds, we obtain the upper bound on the lepton number symmetry breaking scale. The dark matter candidate has unique annihilation channels due to the fact that the theory predicts a light pseudo-Goldstone boson, the Majoron, and one can obtain the correct relic density in a large fraction of the parameter space. In this context, the seesaw scale is below the ${\cal{O}}(10^2)$TeV scale and one can hope to test the origin of neutrino masses at current or future colliders. We discuss the lepton number violating Higgs decays and the possibility to observe lepton number violation at the Large Hadron Collider.

12.Pion quasiparticles in isospin medium from holography

Authors:Weijian Liang, Xuanmin Cao, Hui Liu, Danning Li

Abstract: The properties of the pion quasiparticle in hot and dense isospin medium, including the temperature and isospin chemical potential dependence of their screening mass, pole mass and thermal width, as well as their relationships with the pion superfluid phase transition, are investigated in the framework of two-flavor ($N_{f}=2$) soft-wall AdS/QCD models. We extract the screening mass of the pion from the pole of the spatial two-point Retarded correlation function. We find that the screening masses of both neutral and charged pions increase monotonously with the increasing of temperature. However, the isospin chemical potential $\mu_{I}$ would depress the screening masses of the charged pions, $m_{\pi^{\pm},\rm{scr}}$. With the increasing of $\mu_{I}$, $m_{\pi^{\pm},\rm{scr}}$ monotonically decrease to zero on the boundary between the normal phase and the pion superfluid phase, while the screening mass of the neutral pion, $m_{\pi^0,\rm{scr}}$, remains almost unchanged. The pole mass $m_{\rm{pole}}$ and thermal width $\Gamma$ of the pion are extracted from the pole of temporal two-point Retarded correlation function, i.e., the corresponding quasi-normal frequencies, $\omega=m_{\rm{pole}}-i\Gamma/2$. The results show that the pole masses of the three modes ($\pi^0, \pi^+, \pi^-$) are splitting at finite $\mu_{I}$. The thermal widths of the three modes monotonically increase with temperature. Furthermore, the pole mass of $\pi^+$ decreases almost linearly with the increasing of $\mu_{I}$ and reaches zero at $\mu_{I}=\mu_{I}^c$, It means that $\pi^+$ becomes a massless Goldstone boson of the pion superfluid phase transition.

13.Challenges in Interpreting the NANOGrav 15-Year Data Set as Early Universe Gravitational Waves Produced by ALP Induced Instability

Authors:Michael Geller, Subhajit Ghosh, Sida Lu, Yuhsin Tsai

Abstract: In this paper, we study a possible early universe source for the recent observation of a stochastic gravitational wave background at the NANOGrav pulsar timing array. The source is a tachyonic instability in a dark gauge field induced by an axion-like particle (ALP), a known source for gravitational waves. We find that relative to the previous analysis with the NANOGrav 12.5-year data set, the current 15-year data set favors parameter space with a relatively larger axion mass and decay constant. This favored parameter space is heavily constrained by $\Delta N_{\rm eff}$ and overproduction of ALP dark matter. While there are potential mechanisms for avoiding the second problem, evading the $\Delta N_{\rm eff}$ constraint remains highly challenging. In particular, we find that the gravitational wave magnitude is significantly suppressed with respect to the gauge boson dark radiation, which implies that successfully explaining the NANOGrav observation requires a large additional dark radiation, violating the cosmological constraints.

14.Confronting the 95 GeV excesses within the UN2HDM

Authors:J. A. Aguilar-Saavedra, H. B. Câmara, F. R. Joaquim, J. F. Seabra

Abstract: We consider the small excesses around 95 GeV found in several searches for a new scalar in $\gamma \gamma$, $\tau \tau$ and $b \bar b$ final states. Instead of trying to accommodate them all, as is usually done in the literature, in the context of a given Standard Model~(SM) extension, we investigate whether it would be possible that one or two of these excesses correspond to an actual new scalar, while the remaining ones are merely statistical fluctuations. To this end, we use as benchmark model the UN2HDM, a SM extension with one scalar doublet, one scalar singlet, and an extra $\text{U}(1)'$ symmetry, which has been previously studied in the context of multiboson cascade decays. We show that most of the possibilities where the excesses in one or two of these channels disappear in the future can be accommodated by type-I or type-III UN2HDMs.

15.Transverse momentum dependent feed-down fractions for bottomonium production

Authors:Jacob Boyd, Sabin Thapa, Michael Strickland

Abstract: We extract transverse momentum dependent feed-down fractions for bottomonium production using a data-driven approach. We use data published by the ATLAS, CMS, and LHCb collaborations for sqrt(s) = 7 TeV proton-proton collisions. Based on this collected data, we produce fits to the differential cross sections for the production of both S- and P-wave bottomonium states. Combining these fits with branching ratios for excited state decays from the Particle Data Group, we compute the feed-down fractions for both the Upsilon(1S) and Upsilon(2S) as a function of transverse momentum. Our results indicate a strong dependence on transverse momentum, which is consistent with prior extractions of the feed-down fractions. When evaluated at the average momentum of the states, we find that approximately 75% of Upsilon(1S) and Upsilon(2S) states are produced directly. Our results for the transverse momentum dependent feed-down fractions are provided in tabulated form so that they can be used by other research groups.

1.Heavy flavor conserved semi-leptonic decay of $B_s$ in the covariant light-front approach

Authors:Yu-Ji Shi, Zhi-Peng Xing

Abstract: We study the heavy flavor conserved semi-leptonic decay $B_s\to B\ell\nu$ in the covariant light front approach. The covariant light front quark model is used to calculate the transition form factors of $B_s\to B^{(*)}$ as well as $D_s\to D$, which are consistent with the leading power predictions from the heavy quark symmetry. The angular distribution analysis on the $B_s\to B^{(*)}l\bar\nu$ decay is performed by investigating the forward-backward asymmetry of the lepton. We also study the angular distribution of $B_{s}\to B^{*}(\to B \gamma)l\bar\nu$ decay both through the lepton forward-backward asymmetry and the azimuth angle. The branching fractions of $B_s\to Bl\bar\nu$ and $B_s\to B^{*}l\bar\nu$ are at the order $10^{-8}$ and $10^{-9}$, respectively. The number of $B_s\to B l\bar\nu$ events is estimated to be $1.76$. The branching fraction of $B_{s}\to B^{*}(\to B \gamma)l\bar\nu$ is at the order $10^{-11}$, which is calculated by introducing Breit-Wigner distribution for the intermediate $B^*$.

2.$J/ψ$ Pair Hadroproduction at Next-to-Leading Order in Nonrelativistic-QCD at CMS

Authors:Liping Sun

Abstract: We perform a complete study on the $J/\psi$ pair hadroproduction at next-to-leading order (NLO) in the nonrelativstic-QCD (NRQCD) framework with the pair of $c\bar{c}$ either in ${}^{3}S_1^{[1]}$ or ${}^{1}S_0^{[8]}$ fock state. It is found that the ${}^{1}S_0^{[8]}$ channel contribution at NLO is essential. Our results indicate that for the CMS, the NRQCD predictions can not describe the experimental data at all, and the total cross section predicted by NRQCD is smaller than the experimental data by an order of magnitude. So new mechanisms are needed to understand the CMS data for $J/\psi$ pair production.

3.Several Topics on Transverse Momentum-Dependent Fragmentation Functions

Authors:Kai-Bao Chen, Tianbo Liu, Yu-Kun Song, Shu-Yi Wei

Abstract: The hadronization of a high-energy parton is described by fragmentation functions which are introduced through QCD factorizations. While the hadronization mechanism per se remains uknown, fragmentation functions can still be investigated qualitatively and quantitatively. The qualitative study mainly concentrates on extracting genuine features based on the operator definition in quantum field theory. The quantitative research focuses on describing a variety of experimental data employing the fragmentation function given by the parameterizations or model calculations. With the foundation of the transverse-momentum-dependent factorization, the QCD evolution of leading twist transverse-momentum-dependent fragmentation functions has also been established. In addition, the universality of fragmentation functions has been proven, albeit model-dependently, so that it is possible to perform a global analysis of experimental data in different high-energy reactions. The collective efforts may eventually reveal important information hidden in the shadow of nonperturbative physics. This review covers the following topics: transverse-momentum-dependent factorization and the corresponding QCD evolution, spin-dependent fragmentation functions at leading and higher twists, several experimental measurements and corresponding phenomenological studies, and some model calculations.

4.Pion PDFs confronted by Fixed-Target Charmonium Production

Authors:Wen-Chen Chang, Chia-Yu Hsieh, Yu-Shiang Lian, Jen-Chieh Peng, Stephane Platchkov, Takahiro Sawada

Abstract: The pion, as the Goldstone boson of the strong interaction, is the lightest QCD bound state and responsible for the long-range nucleon-nucleon interaction inside the nucleus. Our knowledge on the pion partonic structure is limited by the existing Drell-Yan data which are primarily sensitive to the pion valence-quark distributions. The recent progress of global analysis of pion's parton distribution functions (PDFs) utilizing various experimental approaches are introduced. From comparisons between the pion-induced $J/\psi$ and $\psi(2S)$ production data with theoretical calculations using the CEM and NRQCD models, we show how these charmonium production data could provide useful constraints on the pion PDFs.

5.Did the nHZ Gravitational Waves Signatures Observed By NANOGrav Indicate Multiple Sector SUSY Breaking?

Authors:Xiao Kang Du, Ming Xia Huang, Fei Wang, Ying Kai Zhang

Abstract: Discrete R symmetries always play an important role in low energy SUSY. The spontaneously broken of such discrete R symmetries, for example, by gaugino condensation, can lead to domain walls, which need to be either inflated away or collapse to avoid cosmic difficulties. We propose that explicitly R symmetry violation needed for collapse of domain walls can be the consequence of multiple sector SUSY breaking. The consistency constraints for the generation of non-problematic domain walls from gaugino condensation are discussed. We also study the emitted gravitational waves related to the collapse of domain walls. We find that, for SUSY breaking scale of order ${\cal O}(1)$ ${\rm GeV}$ in one of the sequestered sector (and also a low reheating temperature of order ${\rm MeV}$ if the reheating is not completed when the domain walls collapse), the peak frequency of gravitational waves emitted can lie at nHz. Such a low SUSY breaking scale can be consistency and natural in multiple sector SUSY breaking scenario. The GWs signal by NANOGrav could be a signal of such multiple sector SUSY breaking scenario and it may also indicate the existences of light goldstini at ${\rm eV}$ mass scale.

6.Analytic results on the massive three-loop form factors: quarkonic contributions

Authors:Johannes Blümlein, Abilio De Freitas, Peter Marquard, Narayan Rana, Carsten Schneider

Abstract: The quarkonic contributions to the three-loop heavy-quark form factors for vector, axial-vector, scalar and pseudoscalar currents are described by closed form difference equations for the expansion coefficients in the limit of small virtualities $q^2/m^2$. A part of the contributions can be solved analytically and expressed in terms of harmonic and cyclotomic harmonic polylogarithms and square-root valued iterated integrals. Other contributions obey equations which are not first-order factorizable. For them still infinite series expansions around the singularities of the form factors can be obtained by matching the expansions at intermediate points and using differential equations which are obeyed directly by the form factors and are derived by guessing algorithms. One may determine all expansion coefficients for $q^2 /m^2 \to \infty$ analytically in terms of multiple zeta values. By expanding around the threshold and pseudo-threshold, the corresponding constants are multiple zeta values supplemented by a finite amount of new constants, which can be computed at high precision. For a part of these coefficients, the infinite series in front of these constants may be even resummed into harmonic polylogarithms. In this way, one obtains a deeper analytic description of the massive form factors, beyond their pure numerical evaluation. The calculations of these analytic results are based on sophisticated computer algebra techniques. We also compare our results with numerical results in the literature.

7.The $D^+_s \to K^+ π^+ π^-$ reaction and the scalar $f_0(500)$, $f_0(980)$ and $K^*_0 (700)$ resonances

Authors:L. R. Dai, E. Oset

Abstract: We develop a model to reproduce the mass distributions of pairs of mesons in the Cabibbo-suppressed $D^+_s \to K^+ \pi^+ \pi^-$ decay. The largest contributions to the process comes from the $D^+_s \to K^+ \rho^0$ and $D^+_s \to K^{*0} \pi^+$ decay modes, but the $D^+_s \to K^*_0(1430) \pi^+$ and $D^+_s \to K^+ f_0(1370)$ modes also play a moderate role and all of them are introduced empirically. Instead, the contribution of the $f_0(500)$, $f_0(980)$ and $K^*_0(700)$ resonances is introduced dynamically by looking at the decay modes at the quark level, hadronizing $q \bar{q}$ pairs to give two mesons, and allowing these mesons to interact to finally produce the $K^+ \pi^+ \pi^-$ final state. These last three modes are correlated by means of only one parameter. We obtain a fair reproduction of the experimental data for the three mass distributions as well as the relative weight of the three light scalar mesons, which we see as further support for the nature of these states as dynamically generated from the interaction of pseudoscalar mesons.

8.Quarkyonic matter and quarkyonic stars in an extended RMF model

Authors:Cheng-Jun Xia, Hao-Miao Jin, Ting-Ting Sun

Abstract: By combining RMF models and equivparticle models with density-dependent quark masses, we construct explicitly ``a quark Fermi Sea'' and ``a baryonic Fermi surface'' to model the quarkyonic phase, where baryons with momentums ranging from zero to Fermi momentums are included. The properties of nuclear matter, quark matter, and quarkyonic matter are then investigated in a unified manner, where quarkyonic matter is more stable and energy minimization is still applicable to obtain the microscopic properties of dense matter. Three different covariant density functionals TW99, PKDD, and DD-ME2 are adopted in our work, where TW99 gives satisfactory predictions for the properties of nuclear matter both in neutron stars and heavy-ion collisions and quarkyonic transition is unfavorable. Nevertheless, if PKDD with larger slope of symmetry energy $L$ or DD-ME2 with larger skewness coefficient $J$ are adopted, the corresponding EOSs are too stiff according to both experimental and astrophysical constraints. The situation is improved if quarkyonic transition takes place, where the EOSs become softer and can accommodate various experimental and astrophysical constraints.

9.Lepton-pair scattering with an off-shell and an on-shell photon at two loops in massless QED

Authors:Simon Badger, Jakub Kryś, Ryan Moodie, Simone Zoia

Abstract: We compute the two-loop QED helicity amplitudes for the scattering of a lepton pair with an off-shell and an on-shell photon, $0\to\ell\bar\ell\gamma\gamma^*$, using the approximation of massless leptons. We express all master integrals relevant for the scattering of four massless particles with a single external off-shell leg up to two loops in a basis of algebraically independent multiple polylogarithms, which guarantees an efficient numerical evaluation and compact analytic representations of the amplitudes. Analytic forms of the amplitudes are reconstructed from numerical evaluations over finite fields. Our results complete the amplitude-level ingredients contributing to the N$^3$LO predictions of electron-muon scattering $e\mu\to e\mu$, which are required to meet the precision goal of the future MUonE experiment.

10.Constraining Post-Inflationary Axions with Pulsar Timing Arrays

Authors:Géraldine Servant, Peera Simakachorn

Abstract: Models that produce Axion-Like-Particles (ALP) after cosmological inflation due to spontaneous $U(1)$ symmetry breaking also produce cosmic string networks. Those axionic strings lose energy through gravitational wave emission during the whole cosmological history, generating a stochastic background of gravitational waves that spans many decades in frequency. We can therefore constrain the axion decay constant and axion mass from limits on the gravitational wave spectrum and compatibility with dark matter abundance as well as dark radiation. We derive such limits from analyzing the most recent NANOGrav data from Pulsar Timing Arrays (PTA). The limits are compatible with the slightly stronger $N_{\rm eff}$ bounds on dark radiation for ALP masses $m_a \lesssim 10^{-10}$ eV. On the other hand, for heavy ALPs with $m_a\gtrsim 0.1$ GeV and $N_{\rm DW}\neq 1$, new regions of parameter space can be probed by PTA data due to the dominant Domain-Wall contribution to the gravitational wave background.

11.Supernova Limits on Muonic Dark Forces

Authors:Claudio Andrea Manzari, Jorge Martin Camalich, Jonas Spinner, Robert Ziegler

Abstract: Proto-neutron stars formed during core-collapse supernovae are hot and dense environments that contain a sizable population of muons. If these interact with new long-lived particles with masses up to roughly 100 MeV, the latter can be produced and escape from the stellar plasma, causing an excessive energy loss constrained by observations of SN 1987A. In this article we calculate the emission of light dark fermions that are coupled to leptons via a new massive vector boson, and determine the resulting constraints on the general parameter space. We apply these limits to the gauged $L_\mu-L_\tau$ model with dark fermions, and show that the SN 1987A constraints exclude a significant portion of the parameter space targeted by future experiments. We also extend our analysis to generic effective four-fermion operators that couple dark fermions to muons, electrons, or neutrinos. We find that SN 1987A cooling probes a new-physics scale up to $\sim7$ TeV, which is an order of magnitude larger than current bounds from laboratory experiments.

12.Neutrinos, Dark Matter and Higgs Vacua in Parity Solutions of the strong CP problem

Authors:Michele Redi, Andrea Tesi

Abstract: The strong CP problem can be solved if the laws of nature are invariant under a space-time parity exchanging the Standard Model with its mirror copy. We review and extend different realizations of this idea with the aim of discussing Dark Matter, neutrino physics, leptogenesis and collider physics within the same context. In the minimal realization of Ref. [1] the mirror world contains a massless dark photon, which leads to a rather interesting cosmology. Mirror electrons reproduce the dark matter abundance for masses between 500-1000 GeV with traces of strongly interacting dark matter. This scenario also predicts deviations from cold dark matter, sizable $\Delta N_{\rm eff}$ and colored states in the TeV range that will be tested in a variety of upcoming experiments. We also explore scenarios where the mirror photon is massive and the mirror particles are charged under ordinary electro-magnetism with very different phenomenology. We also show that, for the measured values of the SM parameters, the Higgs effective potential can give rise to a second minimum at large field value as required to break spontaneously the parity symmetry.

13.Probing the high temperature symmetry breaking with gravitational waves from domain walls

Authors:Xiu-Fei Li

Abstract: The symmetry can be broken at high temperature and then restored at low temperature, which is the so-called \emph{high temperature symmetry breaking}. It often appears in some theories such as the high scale electroweak baryogenesis mechanism. In this paper, we probe the high temperature $\mathbb{Z}_2$ symmetry breaking with gravitational waves (GWs) from domain wall annihilation. We first introduce a scalar with $\mathbb{Z}_2$ symmetry and few of singlet fermions that interact with scalar through a five-dimension operator. This can lead to the scalar potential has a non-zero minimum at high temperature. At the early stage, the scalar is pinned at symmetric phase due to the large Hubble fraction. When the scalar thermal mass becomes comparable to the Hubble parameter, it can quickly roll down to the minimum of potential. Then the $\mathbb{Z}_2$ symmetry is spontaneously broken and the domain walls will form. With the decrease of temperature, $\mathbb{Z}_2$ symmetry will be restored. We find that if domain walls are formed at $\mathcal{O}(10^{9})~ \rm GeV$, the GW produced by domain wall annihilation is expected to be observed by BBO, CE and ET. In addition, we also discuss the relationships between this scenario and NANOGrav signal.

14.The split majoron model confronts the NANOGrav signal

Authors:Pasquale Di Bari, Moinul Hossain Rahat

Abstract: In the light of the evidence of a gravitational wave background from the NANOGrav 15yr data set, we reconsider the split majoron model as a new physics extension of the standard model able to generate a needed contribution to solve the current tension between the data and the standard interpretation in terms of inspiraling supermassive black hole massive binaries. In the split majoron model the seesaw right-handed neutrinos acquire Majorana masses from spontaneous symmetry breaking of global $U(1)_{B-L}$ in a strong first order phase transition of a complex scalar field occurring above the electroweak scale. The final vacuum expectation value couples to a second complex scalar field undergoing a low scale phase transition occurring after neutrino decoupling. Such a coupling enhances the strength of this second low scale first order phase transition and can generate a sizeable primordial gravitational wave background contributing to the NANOGrav 15yr signal. Moreover, the free streaming length of light neutrinos can be suppressed by their interactions with the resulting Majoron background and this can mildly ameliorate existing cosmological tensions, thus providing a completely independent motivation for the model.

15.Fermion Geometry and the Renormalization of the Standard Model Effective Field Theory

Authors:Benoît Assi, Andreas Helset, Aneesh V. Manohar, Julie Pagès, Chia-Hsien Shen

Abstract: The geometry of field space governs on-shell scattering amplitudes. We formulate a geometric description of effective field theories which extends previous results for scalars and gauge fields to fermions. The field-space geometry reorganizes and simplifies the computation of quantum loop corrections. Using this geometric framework, we calculate the fermion loop contributions to the renormalization group equations for bosonic operators in the Standard Model Effective Field Theory up to mass dimension eight.

16.Gravitational Waves, Bubble Profile, and Baryon Asymmetry in the Complex 2HDM

Authors:Dorival Gonçalves, Ajay Kaladharan, Yongcheng Wu

Abstract: This study explores the generation of the observed baryon asymmetry of the Universe within the complex Two Higgs Doublet Model (C2HDM) while considering theoretical and current experimental constraints. In our investigation, we analyze critical elements of the Higgs potential to understand the phase transition pattern. Specifically, we examine the formation of the barrier and the uplifting of the true vacuum state, which play crucial roles in facilitating a strong first-order phase transition. Furthermore, we explore the potential gravitational wave signals associated with this phase transition pattern and investigate the parameter space points that can be probed with LISA. Finally, we compare the impact of different approaches to describing the bubble profile on the calculation of the baryon asymmetry. We contrast the typically used kink profile approximation against the explicit solution of the tunneling profile. We find that a non-negligible range of the C2HDM parameter space results in significant discrepancies in the baryon asymmetry estimation between these two approaches. Through an examination of the parameter space, we identify a benchmark point that satisfies the observed baryon asymmetry.

1.Femtoscopy of $D$ mesons and light mesons upon unitarized effective field theories

Authors:Juan M. Torres-Rincon, Àngels Ramos, Laura Tolos

Abstract: Hadron femtoscopy has turned into a powerful tool for accessing space-time information of heavy-ion collisions as well as for studying final-state interactions of hadrons. Recently, heavy-flavor femtoscopy has become feasible using the ALICE detector at the LHC. We compute the correlation function of $D$ mesons and light mesons using an off-shell $T$-matrix approach to access the two-meson wave function, and predict the correlation functions involving charged $D^+, D^{*+},D_s^+$ and $D_s^{*+}$ with $\pi^\pm$ and $K^\pm$. From the obtained results -- all of them accessible in $p+p$ collision experiments -- we point up the case of $D^+ \pi^-$ which is sensitive to the lower state of the two-pole $D_0^* (2300)$ system. The presence of such poles imprints a depletion on the correlation function, which could potentially be detected in experiments. While preliminary ALICE data do not show evidence of this effect, we suggest to look into the $D_s^+ K^-$ system to explore the higher pole of the $D_0^* (2300)$, as the depletion in the correlation function is more pronounced. Using heavy-quark spin symmetry we also propose exploring the effect of the two poles of the $D_1(2430)$ and predict similar structures in the correlation functions of the $D^{*+} \pi^-$ and $D_s^{*+} K^-$ pairs.

2.A renormalization group improvement for thermally resummed effective potential

Authors:Koichi Funakubo, Eibun Senaha

Abstract: We propose a novel method for renormalization group improvement of thermally resummed effective potential. In our method, $\beta$-functions are temperature dependent as a consequence of the divergence structure in resummed perturbation theory. In contrast to the ordinary $\overline{\text{MS}}$ scheme, the renormalization group invariance of the resummed finite-temperature effective potential holds order by order, which significantly mitigates a notorious renormalization scale dependence of phase transition quantities such as a critical temperature even at the one-loop order. We also devise a tractable method that enables one to incorporate temperature-dependent higher-order corrections by fully exploiting the renormalization group invariance.

3.X17 discovery potential from $γD \to e^+ e^- p n$ with neutron tagging

Authors:Cornelis J. G. Mommers, Marc Vanderhaeghen

Abstract: We propose a novel direct search experiment for X17 using the reaction $\gamma D \to e^+ e^- pn$. X17 is a hypothetical particle conjectured by the ATOMKI collaboration to explain anomalous signals around 17 MeV in excited ${}^8$Be, ${}^4$He and ${}^{12}$C nuclear decays via internal pair creation. It has been subject to a global experimental and theoretical research program. The proposed direct search in $\gamma D \to e^+ e^- pn$ can verify the existence of X17 through the production on a quasi-free neutron, and determine its quantum numbers separate from ongoing and planned nuclear-decay experiments. This is especially timely in view of the theoretical tension between results from the ${}^{12}$C and ${}^8$Be measurements. Using the plane-wave impulse approximation, we quantify the expected signal and background for pseudoscalar, vector and axial-vector X17 scenarios. We optimize the kinematics for the quasi-free neutron region with the upcoming MAGIX experiment at MESA in mind and show that for all three scenarios the X17 signal is clearly visible above the QED background.

4.Electroweak sphalerons, scalar multiplets, and symmetry breaking patterns

Authors:Yanda Wu, Wenxing Zhang, Michael J. Ramsey-Musolf

Abstract: In this study, we present a comprehensive analysis of the electroweak sphaleron formalism and its application to electroweak phase transition (EWPT) patterns in extensions of the Standard Model scalar sector with electroweak multiplets. We offer an equivalence proof for different choices for the form of sphaleron configurations; construct the previously unestablished high-dimensional $\text{SU}(2)$ sphaleron transformation matrix; and revisit the required boundary conditions needed for solving the sphaleron field equations. We then investigate the leading order sphaleron dynamics in the context of a multi-step EWPT. We showcase two distinct analytical approaches for extending the $\text{SU}(2)$ scalar multiplet to the standard model (SM) under differing EWPT scenarios, and perform an explicit calculation of the sphaleron energy using a septuplet example. In the context of a single-step EWPT leading to a mixed phase, we find that the additional multiplet's contribution to the sphaleron energy is negligible, primarily due to the prevailing constraint imposed by the $\rho$ parameter. Conversely, in a two-step EWPT scenario, the sphaleron energy can achieve significantly high values during the initial phase, thereby markedly preserving baryon asymmetry if the universe undergoes a first-order EWPT. In both cases, we delineate the relationship between the sphaleron energy and the parameters relevant to dark matter phenomenology.

5.Spin-1 Thermal Targets for Dark Matter Searches at Beam Dump and Fixed Target Experiments

Authors:Riccardo Catena, Taylor R. Gray

Abstract: The current framework for dark matter searches at beam dump and fixed target experiments relies on four benchmark models, the complex scalar, inelastic scalar, pseudo-Dirac and finally, Majorana DM models. While this approach has so far been successful in the interpretation of the available data, it a priori excludes the possibility that DM is made of spin-1 particles -- a restriction which is neither theoretically nor experimentally justified. In this work we extend the current landscape of sub-GeV DM models to a set of models for spin-1 DM, including a family of simplified models (involving one DM candidate and one mediator -- the dark photon) and an ultraviolet complete model based on a non-abelian gauge group where DM is a spin-1 Strongly Interacting Massive Particle. For each of these models, we calculate the DM relic density, the expected number of signal events at beam dump experiments, the rate of energy injection in the early universe thermal bath and in the Intergalactic Medium, as well as the helicity amplitudes for forward processes subject to the unitary bound. We then compare these predictions with experimental results from Planck, CMB surveys, IGM temperature observations, LSND, MiniBooNE, NA64, and BaBar and with available projections from LDMX and Belle II. Through this comparison, we identify the regions in the parameter space of the models considered in this work where DM is simultaneously thermally produced, compatible with present observations, and within reach at Belle II and LDMX. We find that the simplified models are strongly constrained by current beam dump experiments and the unitarity bound, and will thus be conclusively probed in the first stage of LDMX data taking. We also find that the SIMP model explored in this work predicts the observed DM abundance, is compatible with current observations and within reach at LDMX in a wide region of the parameter space.

6.Resummation of Next-to-Leading Non-Global Logarithms at the LHC

Authors:Thomas Becher, Nicolas Schalch, Xiaofeng Xu

Abstract: In cross sections with angular cuts, an intricate pattern of enhanced higher-order corrections known as non-global logarithms arises. The leading logarithmic terms were computed numerically two decades ago, but the resummation of subleading non-global logarithms remained a challenge that we solve in this Letter using renormalization group methods in effective field theory. To achieve next-to-leading logarithmic accuracy, we implement the two-loop anomalous dimension governing the resummation of non-global logarithms into a large-$N_c$ parton shower framework, together with one-loop matching corrections. As a first application, we study the interjet energy flow in $e^+e^-$ annihilation into two jets. We then present, for the first time, resummed predictions at next-to-leading logarithmic accuracy for a gap-between-jets observable at hadron colliders.

7.Subleading Effects in Soft-Gluon Emission at One-Loop in Massless QCD

Authors:Michał Czakon, Felix Eschment, Tom Schellenberger

Abstract: We elucidate the structure of the next-to-leading-power soft-gluon expansion of arbitrary one-loop massless-QCD amplitudes. The expansion is given in terms of universal colour-, spin- and flavour-dependent operators acting on process-dependent gauge-invariant amplitudes. The result is proven using the method of expansion-by-regions and tested numerically on non-trivial processes with up to six partons. In principle, collinear-region contributions are expressed in terms of convolutions of universal jet operators and process-dependent amplitudes with two collinear partons. However, we evaluate these convolutions exactly for arbitrary processes. This is achieved by deriving an expression for the next-to-leading power expansion of tree-level amplitudes in the double-collinear limit, which is a novel result as well. Compared to previous studies, our analysis, besides being more general, yields simpler formulae that avoid derivatives of process-dependent amplitudes in the collinear limit.

8.$D_s \to f_0$ form factors and the $D_s^+ \to \left[ ππ\right]_{\rm S} e^+ ν_e$ decay from light-cone sum rules

Authors:Shan Cheng, Shu-Lei Zhang

Abstract: In this paper we revisit $D_s \to f_0$ form factors from the light-cone sum rules with the light meson light-cone distribution amplitudes. The main motivation of this study is the differential decay width of $D_s \to \left[\pi\pi \right]_{\rm S} e \nu_e$ measured recently by BESIII collaboration and the $D_s \to f_0$ form factor extracted under the intermediate resonant model. Our result of the differential width of $D_s^+ \to f_0 (\to \left[ \pi\pi \right]_{\rm S}) e^+ \nu_e$ decay obtained under the narrow width approximation is a litter bit lower than the data, the result obtained under the resonant Flatt\'e model is in consistent with the data while shows a litter bit larger, indicating a sizable mixing $\sim 20\degree$ between ${\bar s}s$ and ${\bar u}u+{\bar d}d$ of $f_0$. In order to obtain a model independent prediction, we suggest to calculate $D_s \to \left[ \pi\pi \right]_{\rm S}$ form factors with the isoscalar scalar dipion light-cone distribution amplitudes. Our calculation of $D_s \to \left[ \pi\pi \right]_{\rm S}$ form factors is carried out at the leading twist level due to the finite knowledge of dipion system, the result of differential width shows a moderate evolution in contrast to that obtained from the narrow width approximation and the Flatt\'e model, revealing a bright prospect to study the four-body leptonic decays of heavy mesons with the dimeson light-cone distribution amplitudes.

9.Transverse $Λ$ polarization in $e^+e^-$ annihilations and in SIDIS processes at the EIC within TMD factorization

Authors:Umberto D'Alesio, Leonard Gamberg, Francesco Murgia, Marco Zaccheddu

Abstract: We present a phenomenological study on the role of charm contribution and $SU(2)$ isospin symmetry in the extraction of the $\Lambda$ polarizing fragmentation functions from $e^+e^- \to \Lambda^\uparrow (\bar\Lambda^\uparrow) \,h + X$ annihilation processes. We adopt the well-established transverse-momentum-dependent factorization formalism, within the Collins-Soper-Sterman evolution scheme at next-to-leading logarithm accuracy, carefully exploiting the role of the nonperturbative component of the polarizing fragmentation function. We then discuss the impact of these results on the predictions for transverse $\Lambda$, $\bar{\Lambda}$ polarization in semi-inclusive deep inelastic scattering processes at typical energies of the future Electron-Ion Collider.

10.Constraints on Neutrino Self-Interactions from IceCube Observation of NGC 1068

Authors:Jeffrey M. Hyde

Abstract: The active galaxy NGC 1068 was recently identified by the IceCube neutrino observatory as the first known steady-state, extragalactic neutrino point source, associated with about 79 events over ten years. We use the IceCube data to place limits on possible neutrino self-interactions mediated by scalar particles with mass between 1 - 10 MeV. We find that a flavor-specific $\nu_{\tau}$ self-interaction is constrained beyond existing published bounds, while a flavor-universal self-interaction is not.

11.Evolution of compact states to molecular ones with coupled channels: The case of the $X(3872)$

Authors:Jing Song, L. R. Dai, E. Oset

Abstract: We study the molecular probability of the $X(3872)$ in the $D^0 \bar D^{*0}$ and $D^+ D^{*-}$ channels in several scenarios. One of them assumes that the state is purely due to a genuine nonmolecular component. However, it gets unavoidably dressed by the meson components to the point that in the limit of zero binding of the $D^0 \bar D^{*0}$ component becomes purely molecular. Yet, the small but finite binding allows for a nonmolecular state when the bare mass of the genuine state approaches the $D^0 \bar D^{*0}$ threshold, but, in this case the system develops a small scattering length and a huge effective range for this channel in flagrant disagreement with present values of these magnitudes. Next we discuss the possibility to have hybrid states stemming from the combined effect of a genuine state and a reasonable direct interaction between the meson components, where we find cases in which the scattering length and effective range are still compatible with data, but even then the molecular probability is as big as $95 \%$. Finally, we perform the calculations when the binding stems purely from the direct interaction between the meson-meson components. In summary we conclude, that while present data definitely rule out the possibility of a dominant nonmolecular component, the precise value of the molecular probability requires a more precise determination of the scattering length and effective range of the $D^0 \bar D^{*0}$ channel, as well as the measurement of these magnitudes for the $D^+ D^{*-}$ channel which have not been determined experimentally so far.

12.$ν^2$-Flows: Fast and improved neutrino reconstruction in multi-neutrino final states with conditional normalizing flows

Authors:John Andrew Raine, Matthew Leigh, Knut Zoch, Tobias Golling

Abstract: In this work we introduce $\nu^2$-Flows, an extension of the $\nu$-Flows method to final states containing multiple neutrinos. The architecture can natively scale for all combinations of object types and multiplicities in the final state for any desired neutrino multiplicities. In $t\bar{t}$ dilepton events, the momenta of both neutrinos and correlations between them are reconstructed more accurately than when using the most popular standard analytical techniques, and solutions are found for all events. Inference time is significantly faster than competing methods, and can be reduced further by evaluating in parallel on graphics processing units. We apply $\nu^2$-Flows to $t\bar{t}$ dilepton events and show that the per-bin uncertainties in unfolded distributions is much closer to the limit of performance set by perfect neutrino reconstruction than standard techniques. For the chosen double differential observables $\nu^2$-Flows results in improved statistical precision for each bin by a factor of 1.5 to 2 in comparison to the Neutrino Weighting method and up to a factor of four in comparison to the Ellipse approach.

13.On the two-loop BSM corrections to $h\longrightarrowγγ$ in the aligned THDM

Authors:Giuseppe Degrassi, Pietro Slavich

Abstract: We compute the two-loop BSM contributions to the $h\longrightarrow \gamma\gamma$ decay width in the aligned THDM. We adopt the simplifying assumptions of vanishing EW gauge couplings and vanishing mass of the SM-like Higgs boson, which allow us to exploit a low-energy theorem connecting the $h\gamma\gamma$ amplitude to the derivative of the photon self-energy w.r.t. the Higgs field. We briefly discuss the numerical impact of the newly-computed contributions, showing that they may be required for a precise determination of $\Gamma[h\rightarrow \gamma \gamma]$ in scenarios where the quartic Higgs couplings are large.

14.Probing factorization violation with vector angularities

Authors:Pim Bijl, Steven Niedenzu, Wouter J. Waalewijn

Abstract: Factorization underlies all predictions at the Large Hadron Collider (LHC), but has only been rigorously proven in a few cases. One of these cases is the Drell-Yan process, $pp \to Z/\gamma + X$, in the limit of small boson transverse momentum. We introduce a one-parameter family of observables, that we call vector angularities, of which the transverse momentum is a special case. This enables the study of factorization violation, with a smooth transition to the limit for which factorization has been established. Like the angularity event shapes, vector angularities are a sum of transverse momenta weighted by rapidity, but crucially this is a vector sum rather than a sum of the magnitude of transverse momenta. We study these observables in Pythia, using the effect of multi-parton interactions (MPI) as a proxy factorization violation, finding a negligible effect in the case where factorization is established but sizable effects away from it. We also present a factorization formula for the cross section, that does not include factorization violating contributions from Glauber gluons, and thus offers a baseline for studying factorization violation experimentally using vector angularities. Our predictions at next-to-leading logarithmic accuracy (NLL$'$) are in good in agreement with Pythia (not including MPI), and can be extended to higher order.

15.Correlations of $C$ and $CP$ violation in $η\to π^0\ell^+\ell^-$ and $η'\to η\ell^+\ell^-$

Authors:Hakan Akdag, Bastian Kubis, Andreas Wirzba

Abstract: Based on recent progress in the systematic analysis of $C$ and $CP$ violation in the light-meson sector, we calculate the $C$-odd transition amplitudes $\eta\to\pi^0\ell^+\ell^-$ and $\eta'\to\eta\ell^+\ell^-$. Focusing on long-distance contributions driven by the lowest-lying hadronic intermediate states, we work out the correlations between these beyond-the-Standard-Model signals and the Dalitz-plot asymmetries in $\eta \rightarrow \pi^0 \pi^+ \pi^-$ and $\eta' \rightarrow \eta \pi^+ \pi^- $, using dispersion theory.

16.A phenomenological estimate of isospin breaking in hadronic vacuum polarization

Authors:Martin Hoferichter, Gilberto Colangelo, Bai-Long Hoid, Bastian Kubis, Jacobo Ruiz de Elvira, Dominic Schuh, Dominik Stamen, Peter Stoffer

Abstract: Puzzles in the determination of the hadronic-vacuum-polarization contribution currently impede a conclusive interpretation of the precision measurement of the anomalous magnetic moment of the muon at the Fermilab experiment. One such puzzle concerns tensions between evaluations in lattice QCD and using $e^+e^-\to\text{hadrons}$ cross-section data. In lattice QCD, the dominant isospin-symmetric part and isospin-breaking (IB) corrections are calculated separately, with very different systematic effects. Identifying these two pieces in a data-driven approach provides an opportunity to compare them individually and trace back the source of the discrepancy. Here, we estimate the IB component of the lattice-QCD calculations from phenomenology, based on a comprehensive study of exclusive contributions that can be enhanced via infrared singularities, threshold effects, or hadronic resonances, including, for the first time, in the $e^+e^-\to3\pi$ channel. We observe sizable cancellations among different channels, with a sum that even suggests a slightly larger result for the QED correction than obtained in lattice QCD. We conclude that the tensions between lattice QCD and $e^+e^-$ data therefore cannot be explained by the IB contributions in the lattice-QCD calculations.

17.Isospin-breaking effects in the three-pion contribution to hadronic vacuum polarization

Authors:Martin Hoferichter, Bai-Long Hoid, Bastian Kubis, Dominic Schuh

Abstract: Isospin-breaking (IB) effects are required for an evaluation of hadronic vacuum polarization at subpercent precision. While the dominant contributions arise from the $e^+e^-\to\pi^+\pi^-$ channel, also IB in the subleading channels can become relevant for a detailed understanding, e.g., of the comparison to lattice QCD. Here, we provide such an analysis for $e^+e^-\to 3\pi$ by extending our dispersive description of the process, including estimates of final-state radiation (FSR) and $\rho$-$\omega$ mixing. In particular, we develop a formalism to capture the leading infrared-enhanced effects in terms of a correction factor $\eta_{3\pi}$ that generalizes the analog treatment of virtual and final-state photons in the $2\pi$ case. The global fit to the $e^+e^-\to 3\pi$ data base, subject to constraints from analyticity, unitarity, and the chiral anomaly, gives $a_\mu^{3\pi}|_{\leq 1.8\,\text{GeV}}=45.91(53)\times 10^{-10}$ for the total $3\pi$ contribution to the anomalous magnetic moment of the muon, of which $a_\mu^\text{FSR}[3\pi]=0.51(1)\times 10^{-10}$ and $a_\mu^{\rho\text{-}\omega}[3\pi]=-2.68(70)\times 10^{-10}$ can be ascribed to IB. We argue that the resulting cancellation with $\rho$-$\omega$ mixing in $e^+e^-\to 2\pi$ can be understood from a narrow-resonance picture, and provide updated values for the vacuum-polarization-subtracted vector-meson parameters $M_\omega=782.70(3)\,\text{MeV}$, $M_\phi=1019.21(2)\,\text{MeV}$, $\Gamma_\omega=8.71(3)\,\text{MeV}$, and $\Gamma_\phi=4.27(1)\,\text{MeV}$.

18.Falsifying Pati-Salam models with LIGO

Authors:Peter Athron, Csaba Balázs, Tomás E. Gonzalo, Matthew Pearce

Abstract: We demonstrate that existing gravitational wave data from LIGO already places constraints on well motivated Pati-Salam models that allow the Standard Model to be embedded within grand unified theories. For the first time in these models we also constrain the parameter space by requiring that the phase transition completes, with the resulting constraint being competitive with the limits from LIGO data. Both constraints are complementary to the LHC constraints and can exclude scenarios that are much heavier than can be probed in colliders. Finally we show that results from future LIGO runs, and the planned Einstein telescope, will substantially increase the limits we place on the parameter space.

19.Heavy neutral lepton corrections to SM boson decays: lepton flavour universality violation in low-scale seesaw realisations

Authors:A. Abada, J. Kriewald, E. Pinsard, S. Rosauro-Alcaraz, A. M. Teixeira

Abstract: We study lepton flavour universality violation in SM boson decays in low-scale seesaw models of neutrino mass generation, also addressing other electroweak precision observables. We compute the electroweak next-to-leading order corrections, which turn out to be important - notably in the case of the invisible decay width of the $Z$ boson, for which the corrections can be as large as the current experimental uncertainty. As a well-motivated illustrative study case, we choose a realisation of the Inverse Seesaw mechanism, and discuss the complementary role of lepton flavour conserving, lepton flavour violating and precision observables, both in constraining and in probing such models of neutrino mass generation. Our findings suggest that invisible $Z$ decays are especially important, potentially at the origin of the most stringent constraints for certain regimes of the Inverse Seesaw (while complying with charge lepton flavour violation and other electroweak precision tests). We also discuss the probing power of the considered observables in view of the expected improvement in experimental precision at FCC-ee.

20.Matter-antimatter asymmetry and dark matter stability from baryon number conservation

Authors:Mar Císcar-Monsalvatje, Alejandro Ibarra, Jérôme Vandecasteele

Abstract: There is currently no evidence for a baryon asymmetry in our Universe. Instead, cosmological observations have only demonstrated the existence of a quark-antiquark asymmetry, which does not necessarily imply a baryon asymmetric Universe, since the baryon number of the dark sector particles is unknown. In this paper we discuss a framework where the total baryon number of the Universe is equal to zero, and where the observed quark-antiquark asymmetry arises from neutron portal interactions with a dark sector fermion $N$ that carries baryon number. In order to render a baryon symmetric universe throughout the whole cosmological history, we introduce a complex scalar $\chi$, with opposite baryon number and with the same initial abundance as $N$. Notably, due to the baryon number conservation, $\chi$ is absolutely stable and could have an abundance today equal to the observed dark matter abundance. Therefore, in this simple framework, the existence of a quark-antiquark asymmetry is intimately related to the existence (and the stability) of dark matter.

21.The Postdoc Accord in Theoretical High Energy Physics

Authors:Djuna Croon, Patrick J. Fox, Roni Harnik, Simon Knapen, Mariangela Lisanti, Lina Necib, Tien-Tien Yu

Abstract: We present the results of a survey meant to assess the opinion of the high-energy physics theory (HET) community on the January 7th postdoc acceptance deadline - specifically, whether there is a preference to shift the deadline to later in January or February. This survey, which served for information-gathering purpose only, is part of a community conversation on the optimal timing of an acceptance deadline and whether the community would be better served by a later date. In addition, we present an analysis of data from the postdoc Rumor Mill, which gives a picture of the current hiring landscape in the field. We emphasize the importance of preserving a universal deadline, and the current results of our survey show broad support for a shift to a later date. A link to the survey, frequently asked questions, a running list of supporters, and next steps can be found on our companion web page.

1.Fermion Hierarchies in $SU(5)$ Grand Unification from $Γ_6^\prime$ Modular Flavor Symmetry

Authors:Yoshihiko Abe, Tetsutaro Higaki, Junichiro Kawamura, Tatsuo Kobayashi

Abstract: We construct a model in which the hierarchies of the quark and lepton masses and mixing are explained by the $\Gamma_6^\prime$ modular flavor symmetry. The hierarchies are realized by the Froggatt-Nielsen-like mechanism due to the residual $Z^T_6$ symmetry, approximately unbroken at $\tau \sim i\infty.$ We argue that the $\Gamma_6^{(\prime)}$ symmetry is the minimal possibility to realize the up-type quark mass hierarchies, since the Yukawa matrix is symmetric. We find a combination of the representations and modular weights and then show numerical values of $\mathcal{O}(1)$ coefficients for the realistic fermion hierarchies.

2.Exploring the higher-order QED effects on the differential distributions of Breit-Wheeler process in relativistic heavy-ion collisions

Authors:Xinbai. Li, Jiaxuan. Luo, Zebo. Tang, Xin. Wu, Wangmei. Zha

Abstract: Extensive studies have been conducted in the past few decades to investigate potential signatures of higher-order QED effects in high-energy electromagnetic scattering processes. In our previous work, we have identified evidence of higher-order corrections in the total cross-section for the Breit-Wheeler process in relativistic heavy-ion collisions. However, the presence of higher-order QED corrections cannot be unambiguously proven solely based on total cross-section measurements due to substantial experimental and theoretical uncertainties. The objective of this paper is to explore the sensitivity of specific differential observables in the Breit-Wheeler process to higher-order QED effects in high-energy heavy-ion collisions. These investigations will provide guidance in determining the presence or absence of higher-order QED processes by conducting precise measurements in future experiments.

3.Collider physics with no PDFs

Authors:Tuomas Lappi, Heikki Mäntysaari, Hannu Paukkunen, Mirja Tevio

Abstract: Measurements of Deep Inelastic Scattering (DIS) provide a powerful tool to probe the fundamental structure of protons and other nuclei. The DIS cross sections can be expressed in terms of structure functions which are conventionally expressed in terms of parton distribution functions (PDFs) that obey the DGLAP evolution equations. However, it is also possible to formulate the DGLAP evolution directly in terms of measurable DIS structure functions entirely sidestepping the need for introducing PDFs. We call this as the physical-basis approach. In a global analysis one would thereby directly parametrize the (observable) structure functions -- not the (unobservable) PDFs. Ideally, with data constraints at fixed $Q^2$, the initial condition for the evolution would be the same at each perturbative order (unlike for PDFs) and the approach thus provides a more clean test of the QCD dynamics. We first study a physical basis consisting of the structure functions $F_2$ and $F_{\rm L}$ in the fixed-flavour number scheme to the leading non-zero order in $\alpha_s$. We show how to express the quark singlet and gluon PDFs in terms of $F_2$ and $F_{\rm L}$ directly in momentum space which then leads to the DGLAP evolution of the structure functions $F_2$ and $F_{\rm L}$. In the second step we expand the physical basis to include six independent structure functions, which allows for a consistent global analysis. The steps towards NLO accuracy and the variable-flavour-number scheme are outlined. At NLO accuracy (when the scheme dependence of PDFs starts to play a part), we can take advatage of the physical basis and express e.g. the Drell-Yan cross sections at the LHC directly in terms of measurable DIS structure functions and thus without the scheme dependence.

4.Testing Complex Singlet Scalar Cosmology at the Large Hadron Collider

Authors:Wenxing Zhang, Yizhou Cai, Michael J. Ramsey-Musolf, Lei Zhang

Abstract: The Standard Model extended with a complex singlet scalar (cxSM) can admit a strong first order electroweak phase transition (SFOEWPT) as needed for electroweak baryogenesis and provide a dark matter (DM) candidate. The presence of both a DM candidate and a singlet-like scalar that mixes with the Standard Model Higgs boson leads to the possibility of a $b\bar{b}+\text{MET}$ final state in $pp$ collisions. Focusing on this channel, we analyze the prospective reach at the Large Hadron Collider (LHC) for a heavy singlet-like scalar in regions of cxSM parameter space compatible with a SFOEWT and DM phenomenology. We identify this parameter space while implementing current constraints from electroweak precision observable and Higgs boson property measurements as well as those implied by LHC heavy resonance searches.

5.Relations between basis sets of fields in the renormalization procedure

Authors:Simonas Draukšas

Abstract: It seems that the literature suggests to go in two opposing directions simultaneously. On the one hand, many papers construct basis-independent quantities, since exactly these quantities appear in the expressions for observables. This means that the mixing angles such as $\tan \beta$ in the Two Higgs Doublet Model must drop out when calculating anything physical. On the other hand, there are many attempts to renormalize such mixing angles -- this is in the opposite direction to basis-independence. This basis-dependent approach seems to bring gauge-dependence and singular behaviour, both of which are required to be absent in mixing renormalization. Most importantly, mixing angle counterterms single out a preferred basis and further basis rotations lead to inconsistencies. In contrast, we argue that the bare mixing angles should be identified with the renormalized ones -- this is the basis-independent approach -- such that all the mixing renormalization requirements are fulfilled in a trivial and consistent manner.

6.Holographic baryons, dense matter and neutron star mergers

Authors:Matti Jarvinen

Abstract: The gauge/gravity duality, combined with information from lattice QCD, nuclear theory, and perturbative QCD, can be used to constrain the equation of state of hot and dense QCD. I discuss an approach based on the holographic V-QCD model. I start by reviewing the results from the construction of the V-QCD baryon as a soliton of the gauge fields in the model. Then I discuss implementing nuclear matter in the model by using a homogeneous approach. The model predicts a strongly first order phase transition from nuclear to quark matter with a critical endpoint. By using the model in state-of-the-art simulations of neutron star binaries with parameters consistent with GW170817, I study the formation of quark matter during the merger process.

7.On evolution kernels of twist-two operators

Authors:Yao Ji, Alexander Manashov, Sven-Olaf Moch

Abstract: The evolution kernels that govern the scale dependence of the generalized parton distributions are invariant under transformations of the $\mathrm{SL}(2,\mathrm R)$ collinear subgroup of the conformal group. Beyond one loop the symmetry generators, due to quantum effects, differ from the canonical ones. We construct the transformation which brings the {\it full} symmetry generators back to their canonical form and show that the eigenvalues (anomalous dimensions) of the new, canonically invariant, evolution kernel coincide with the so-called parity respecting anomalous dimensions. We develop an efficient method that allows one to restore an invariant kernel from the corresponding anomalous dimensions. As an example, the explicit expressions for NNLO invariant kernels for the twist two flavor-nonsinglet operators in QCD and for the planar part of the universal anomalous dimension in $ N=4$ SYM are presented.

8.Quantum simulation of in-medium QCD jets: momentum broadening, gluon production, and entropy growth

Authors:João Barata, Xiaojian Du, Meijian Li, Wenyang Qian, Carlos A. Salgado

Abstract: Jets provide one of the primary probes of the quark-gluon plasma produced in ultrarelativistic heavy ion collisions and the cold nuclear matter explored in deep inelastic scattering experiments. However, despite important developments in the last years, a description of the real-time evolution of QCD jets inside a medium is still far from being complete. In our previous work, we have explored quantum technologies as a promising alternative theoretical laboratory to simulate jet evolution in QCD matter, to overcome inherent technical difficulties in present calculations. Here, we extend our previous investigation from the single particle $|q\rangle$ to the $|q\rangle+|qg\rangle$ Fock space, taking into account gluon production. Based on the light-front Hamiltonian formalism, we construct a digital quantum circuit that tracks the evolution of a multi-particle jet probe in the presence of a medium described as a stochastic color field. Studying the momentum broadening of the jet state, we observe sizable sub-eikonal effects by comparing to eikonal estimates. We also study the medium-induced modifications to the gluon emission probability, which exhibit small corrections compared to the vacuum splitting function. In addition, we study the time evolution of the von-Neumann entropy associated with the quark component; we find that the exponential of the entropy grows linearly in time for the bare quark but super-linearly when taking into account gluon emission.

9.Composite Hybrid Inflation: Dilaton and Waterfall Pions

Authors:Giacomo Cacciapaglia, Dhong Yeon Cheong, Aldo Deandrea, Wanda Isnard, Seong Chan Park

Abstract: We investigate the possibility that inflation originates from a composite field theory, in terms of an effective chiral Lagrangian involving a dilaton and pions. The walking dynamics of the theory constrain the potential in a specific way, where the anomalous dimensions of operators involving pions play a crucial role. For realistic values of the anomalous dimensions, we find a successful hybrid inflation occurring via the dilaton-inflaton, with the pions acting as waterfall fields. Compositeness consistency strongly constrain the model, predicting a dilaton scale $f_\chi \sim \mathcal{O} (1)$ in unit of the Planck scale, an inflation scale $H_\text{inf} \sim 10^{10}$ GeV, and the pion scale around $10^{14}$ GeV. We further discuss possible phenomenological consequences of this theory.

10.Long-Lived Particles and the Quiet Sun

Authors:R. Andrew Gustafson, Ryan Plestid, Ian M. Shoemaker, Albert Zhou

Abstract: The nuclear reaction network within the interior of the Sun is an efficient MeV physics factory, and can produce long-lived particles generic to dark sector models. In this work we consider the sensitivity of satellite instruments, primarily the RHESSI Spectrometer, that observe the Quiet Sun in the MeV regime where backgrounds are low. We find that Quiet Sun observations offer a powerful and complementary probe in regions of parameter space where the long-lived particle decay length is longer than the radius of the Sun, and shorter than the distance between the Sun and Earth. We comment on connections to recent model-building work on heavy neutral leptons coupled to neutrinos and high-quality axions from mirror symmetries.

11.Resonance $X(7300)$: excited $2S$ tetraquark or hadronic molecule $χ_{c1}χ_{c1}$?

Authors:S. S. Agaev, K. Azizi, B. Barsbay, H. Sundu

Abstract: We explore the first radial excitation $X_{\mathrm{4c}}^{\ast}$ of the fully charmed diquark-antidiquark state $X_{\mathrm{4c}}=cc\overline{c}\overline{c} $ built of axial-vector components, and the hadronic molecule $\mathcal{M} =\chi_{c1}\chi_{c1}$. The masses and current couplings of these scalar states are calculated in the context of the QCD two-point sum rule approach. The full widths of $X_{\mathrm{4c}}^{\ast}$ and $\mathcal{M}$ are evaluated by taking into account their kinematically allowed decay channels. We find partial widths of these processes using the strong couplings $g_i^{\ast}$ and $G_i^{(\ast)}$ at the $X_{\mathrm{4c}}^{\ast}$($\mathcal{M}$ )-conventional mesons vertices computed by means of the QCD three-point sum rule method. The predictions obtained for the parameters $m=(7235 \pm 75)~ \mathrm{MeV}$, $\Gamma=(144 \pm 18)~\mathrm{MeV}$ and $\widetilde{m}=(7180 \pm 120)~\mathrm{MeV}$, $\widetilde{\Gamma}=(169 \pm 21)~\mathrm{MeV}$ of these structures, are compared with the experimental data of the CMS and ATLAS Collaborations. In accordance with this analysis, the radially excited tetraquark $X_{\mathrm{4c}}^{\ast}$ is promising candidate to the resonance $ X(7300)$, though we do not exclude the molecule or mixed tetraquark-molecule model for this state.

12.Unveiling the Heavy Neutrino Nature at LHCb

Authors:G. A. Vasquez University of Victoria, Jilberto Zamora-Saa Universidad Andres Bello

Abstract: In this work, we study the lepton number violating Bc meson decays via one intermediate on-shell heavy neutrino. The specific studied process is $B_{c}^{+} \to \mu^{+} \ N \to \mu^{+} \mu^{+} \tau^{-} \nu$ which could allow distinguishing the nature of the heavy neutrino nature (Dirac or Majorana) by studying the tau lepton energy spectrum in the LHCb experiment. The result suggests that this signature could be observed in the collected data during the HL-LHCb lifetime.

1.The hidden strange $B_{c}$-like molecular states

Authors:Zhong-Yu Wang, Zhi-Feng Sun

Abstract: With the chiral unitary approach, we evaluate the hidden strange $B_{c}$-like molecular states of $b\bar{c}s\bar{s}$ systems $\bar{B}_{s}\bar{D}_{s}$, $\bar{B}_{s}^{*}\bar{D}_{s}$, $\bar{B}_{s}\bar{D}_{s}^{*}$, and $\bar{B}_{s}^{*}\bar{D}_{s}^{*}$ coupled to the non-strange channels. The $S$-wave scattering amplitudes are calculated based on the vector meson exchange, four pseudoscalar mesons contact interactions, and four vector mesons contact interactions obtained from the extended local hidden gauge approach. We find six states below the threshold of the most relevant channel. The binding energies of these states are around $1-10$ MeV and the widths are around $0.2-0.7$ MeV. Our research is a supplement to the mass spectra of $B_{c}$-like states, which may be useful for the experimental search in the future.

2.New Method for Measuring the Ratio $μ_p G_E/G_M$ Based on the Polarization Transfer from the Initial Proton to the Final Electron in the $e \vec p \to \vec e p$ Process

Authors:M. V. Galynskii, Yu. M. Bystritskiy, V. M. Galynsky

Abstract: In this letter, we propose a new method for measuring the Sachs form factors ratio ($R =\mu_p G_E/G_M$) based on the transfer of polarization from the initial proton to the final electron in the elastic $e \vec p \to \vec e p$ process, in the case when the axes of quantization of spins of the target proton at rest and of the scattered electron are parallel, i.e., when an electron is scattered in the direction of the spin quantization axis of the proton target. To do this, in the kinematics of the SANE collaboration experiment (2020) on measuring double spin asymmetry in the $\vec e\vec p \to e p$ process, using Kelly (2004) and Qattan (2015) parametrizations, a numerical analysis was carried out of the dependence of the longitudinal polarization degree of the scattered electron on the square of the momentum transferred to the proton, as well as on the scattering angles of the electron and proton. It is established that the difference in the longitudinal polarization degree of the final electron in the case of conservation and violation of scaling of the Sachs form factors can reach 70%. This fact can be used to set up polarization experiments of a new type to measure the ratio $R$.

3.Resonant screening in dense and magnetized QCD matter

Authors:Guojun Huang, Jiaxing Zhao, Pengfei Zhuang

Abstract: We calculate the Debye screening mass in thermal, dense and magnetized QCD matter in the frame of resummed perturbation theory. In the limit of zero temperature, when the Landau energy level and Fermi surface of quarks match each other $\mu_q^2=2n|qB|$, where $q$, $\mu_q$ and $B$ are respectively the quark electric charge, chemical potential and external magnetic field, the screening mass diverges and the system is in the state of weakly interacting parton gas, which is very different from the known result of strongly interacting quark-gluon plasma at high temperature. The divergence disappears in thermal medium, but the screening mass oscillates with clear peaks at the matched magnetic field.

4.Innovative Polarimetry for High$-$energy Cosmic $γ$ and $e^{+}/e^{-}$ Induced by Vector Photo$-$productionn

Authors:Dart-yin A. Soh, Zhaoyi Qu

Abstract: In this paper, we explore the possibility of measuring the complete polarizations of cosmic photons $\gamma$ and the polarizations of cosmic electrons $e^{-}$ and positrons $e^{+}$. Our innovative Vector Meson Photo-production induced polarimetry enables people to measure the circular plarization compoent of a $GeV$ $\gamma$ and to improve its linear polarization measurement, and thus enables people to measure the polarization of $GeV$ $e^{+}/e^{-}$ for the first time. We calculate the production process of $\pi^{+}\pi^{-}$ by a generally polarized photon near nucleon's field in a generalized VPD-SDMEs Factorization with the fitted experimental data, so that it's partially model-independent. We also propose the observables and approach to measure their polarizations based on our calculations. Our new polarimetry of high-energy cosmic $\gamma,e^{+},e^{-}$ will open a new window to reveal the mysteries and solve the puzzles of BSM new physics in particle physics and cosmology.

5.Implications of Nano-Hertz Gravitational Waves on Electroweak Phase Transition in the Singlet Dark Matter Model

Authors:Yang Xiao, Jin Min Yang, Yang Zhang

Abstract: Inspired by the recent evidences of nano-Hertz stochastic gravitational waves observed by the pulsar timing array collaborations, we explore their implied supercooled electroweak phase transition in the singlet extension of the Standard Model. Our findings reveal that by adjusting the model parameter at per milli level, the corresponding percolation temperature can be continuously lowered to 1 GeV. With such a low percolation temperature, the singlet dark matter may freeze out before the electroweak phase transition, and, consequently, the entropy generated during the transition can significantly affect the dark matter relic density and other related constraints.

6.A collider test of nano-Hertz gravitational waves from pulsar timing arrays

Authors:Shao-Ping Li, Ke-Pan Xie

Abstract: A cosmic first-order phase transition (FOPT) occurring at MeV-scale provides an attractive explanation for the nano-Hertz gravitational wave (GW) background indicated by the recent pulsar timing array data from the NANOGrav, CPTA, EPTA and PPTA collaborations. We propose this explanation can be further tested at the colliders if the hidden sector couples to the Standard Model sector via Higgs portal. Through a careful analysis of the thermal history of the hidden sector, we demonstrate that in order to successfully explain the observed GW signal, the portal coupling must be sizable that it can be probed through Higgs invisible decay at the LHC or future lepton colliders such as CEPC, ILC, and FCC-ee. Our research offers a promising avenue to uncover the physical origin of the nano-Hertz GWs through particle physics experiments.

7.Fuzzy Dark Matter, the Dark Dimension, and the Pulsar Timing Array Signal

Authors:Luis A. Anchordoqui, Ignatios Antoniadis, Dieter Lust

Abstract: We propose a new dark matter contender within the context of the so-called ``dark dimension'', an innovative 5-dimensional construct that has a compact space with characteristic length-scale in the micron range. The new dark matter candidate is the radion, a bulk scalar field whose quintessence-like potential drives an inflationary phase described by a 5-dimensional de Sitter (or approximate) solution of Einstein equations. We show that the radion could be ultralight and thereby serve as a fuzzy dark matter candidate. We advocate a simple cosmological production mechanism bringing into play unstable Kaluza-Klein graviton towers which are fueled by the decay of the inflaton. We demonstrate that the fuzzy radion can accommodate the signal recently observed in pulsar timing arrays.

8.Pinning down the leptophobic $Z^\prime$ in leptonic final states with Deep Learning

Authors:Tanumoy Mandal, Aniket Masaye, Subhadip Mitra, Cyrin Neeraj, Naveen Reule, Kalp Shah

Abstract: A leptophobic $Z^\prime$ that does not couple with the Standard Model leptons can evade the stringent bounds from the dilepton-resonance searches. In our earlier paper [T. Arun et al., Search for the $Z'$ boson decaying to a right-handed neutrino pair in leptophobic $U(1)$ models, Phys. Rev. D, 106 (2022) 095035; arXiv:2204.02949], we presented two gauge anomaly-free $U(1)$ models where a heavy leptophobic $Z'$ is present along with right-handed neutrinos ($N_R$). We pointed out the interesting possibility of a correlated search for $Z'$ and $N_R$ at the LHC through the $pp\to Z'\to N_R N_R$ channel. This channel can probe a part of the leptophobic $Z'$ parameter space that cannot be otherwise probed using the standard dijet resonance searches. In this paper, we analyse the monolepton final state arising from the decay of the $N_R$ pair. We show that a leptophobic $Z'$ as heavy as $7$ TeV and with a gauge coupling of the order of the electroweak coupling is discoverable through this channel at the high-luminosity LHC.

9.The Standard Model theory of neutron beta decay

Authors:Mikhail Gorchtein, Chien-Yeah Seng

Abstract: We review the status of the Standard Model theory of neutron beta decay. Particular emphasis is put on the recent developments in the electroweak radiative corrections. Given that some existing approaches give slightly different results, we thoroughly review the origin of discrepancies, and provide our recommended value for the radiative correction to the neutron and nuclear decay rates. The use of dispersion relation, lattice Quantum Chromodynamics and effective field theory framework allows for high-precision theory calculations at the level of $10^{-4}$, turning neutron beta decay into a powerful tool to search for new physics, complementary to high-energy collider experiments. We offer an outlook to the future improvements.

10.Extraction of the strong coupling with HERA and EIC inclusive data

Authors:Salim Cerci, Zuhal Seyma Demiroglu, Abhay Deshpande, Paul R. Newman, Barak Schmookler, Deniz Sunar Cerci, Katarzyna Wichmann

Abstract: The sensitivity to the strong coupling $\alpha_S(M^2_Z)$ is investigated using existing Deep Inelastic Scattering data from HERA in combination with projected future measurements from the Electron Ion Collider (EIC) in a next-to-next-to-leading order QCD analysis. A potentially world-leading level of precision is achievable when combining simulated inclusive neutral current EIC data with inclusive charged and neutral current measurements from HERA, with or without the addition of HERA inclusive jet and dijet data. The result can be obtained with significantly less than one year of projected EIC data at the lower end of the EIC centre-of-mass energy range. Some questions remain over the magnitude of uncertainties due to missing higher orders in the theoretical framework.

11.HNL see-saw: lower mixing limit and pseudodegenerate state

Authors:Igor Krasnov

Abstract: Heavy Neutral Leptons are popular hypothetical particles, first introduced as a way to explain neutrino oscillations, and since then extensively studied in relation to many other aspects of physics beyond the Standard Model. They also serve as viable targets for direct experimental searches, being effectively described only by HNL mass and mixing with each neutrino flavor. Motivated by this, we study the lower theoretical boundary for mixing with a specified flavor in two and three HNL cases. We find the connection of this limit with the effective neutrino mass appearing in neutrinoless double beta decay (and similar expressions for mixing with muon and tau neutrino). In two HNL case, there is a rather strict relation between mixing of different HNL with the same neutrino flavor. We find that existing exclusion regions and their expected expansions in the near future are all described by a certain limit. We call that limit pseudodegenerate and find its relation to the symmetrical limit, already studied in the literature. We also study pseudodegenerate limit and conditions under which it is achieved in three HNL case.

12.NANOGrav signal from axion inflation

Authors:Xuce Niu, Moinul Hossain Rahat

Abstract: Several pulsar timing arrays have recently reported the observation of a stochastic background of red-tilted gravitational wave spectrum in the nano-Hz frequencies. An inflationary interpretation of this observation is challenging from various aspects. We report that such a signal can arise from Chern-Simons coupling in axion inflation, where a pseudoscalar inflaton couples to (massive) $U(1)$ gauge field, leading to efficient production of a transverse gauge mode. Such tachyonic particle production during inflation exponentially enhances the primordial perturbations and leads to a unique parity-violating gravitational wave spectrum, that remains flat near the CMB scales but becomes red-tilted at smaller scales. We identify the parameter space consistent with various cosmological constraints and show that the resultant gravitational wave signals can explain the observed excess at NANOGrav.

13.Minimal Inert Doublet Benchmark for Dark Matter and the Baryon Asymmetry

Authors:María Dias Astros, Sven Fabian, Florian Goertz

Abstract: In this article we discuss a minimal extension of the Inert Doublet Model (IDM) with an effective $CP$-violating $D=6$ operator, involving the inert Higgs and weak gauge bosons, that can lift it to a fully realistic setup for creating the baryon asymmetry of the Universe (BAU). Avoiding the need to stick to an explicit completion, we investigate the potential of such an operator to give rise to the measured BAU during a multi-step electroweak phase transition (EWPhT) while sustaining a viable DM candidate in agreement with the measured relic abundance. We find that the explored extension of the IDM can account quantitatively for both DM and for baryogenesis and has quite unique virtues, as we will argue. It can thus serve as a benchmark for a minimal realistic extension of the SM that solves some of its shortcomings and could represent the low energy limit of a larger set of viable completions. After discussing the impact of a further class of operators that open the possibility for a larger mass splitting (enhancing the EWPhT) while generating the full relic abundance also for heavy inert-Higgs DM, we ultimately provide a quantitative evaluation of the induced lepton electric dipole moments in the minimal benchmark for the BAU. These arise here at the two-loop level and are therefore less problematic compared to the ones that emerge when inducing $CP$ violation via an operator involving the SM-like Higgs.

14.Sensitivities on the anomalous quartic $γγγγ$ and $γγγZ$ couplings at the CLIC

Authors:E. Gurkanli

Abstract: It is essential to directly investigate the self-couplings of gauge bosons in the Standard Model (SM) due to its non-Abelian nature, as these couplings play a significant role in comprehending the gauge structure of the model. The discrepancies between the Standard Model's expectations and the measured value of gauge boson self-couplings would serve as strong evidence towards the existence of new physics phenomena that extend beyond the Standard Model. Such deviations could provide valuable insights into the nature of new physics and potentially lead to a deeper understanding of fundamental particles and their interactions. In this study, we examine the sensitivities of anomalous couplings associated with dimension-8 operators that affect the $\gamma \gamma \gamma \gamma$ and $Z \gamma \gamma \gamma$ quartic vertices. The study focuses on the process $e^- \gamma \to e^-\gamma\gamma$ with the incoming photon under Weizs\"acker-Williams approximation at the stage-3 scenerio of Compact Linear Collider (CLIC) that is refer to a CoM energy of 3 TeV. Due to the CLIC options, we take into account the both unpolarized and $\mp80\%$ polarized electron beam with the related integrated luminosities of ${\cal L}=5, 4, 1$ $\rm ab^{-1}$ under the systematic uncertainties of $\delta_{sys}=0, 3, 5$. Obtained sensitivities on the anomalous quartic gauge couplings (aQGCs) for the process $e^- \gamma \to e^-\gamma\gamma$ at $\sqrt{s}= 3$ TeV and various polarizations, are improved by a factor of 2-200 times better for the couplings $f_{T,j}/\Lambda^4$ compared with the experimental results.

15.The alpha particle charge radius, the radion and the proton radius puzzle

Authors:F. Dahia, A. S. Lemos

Abstract: Recent measurements of the Lamb shift of muonic helium-4 ions were used to infer the alpha particle charge radius. The value found is compatible with the radius extracted from the analysis of the electron-helium scattering. Thus, the new spectroscopic data put additional empiric bounds on some free parameters of certain physics theories beyond the Standard Model. In this paper, we analyze the new data in the context of large extra-dimensional theories. Specifically, we calculate the influence of the radion, the scalar degree of freedom of the higher-dimensional gravity, on the energy difference between the 2S and 2P levels of this exotic atom. The radion field is related to fluctuations of the volume of the supplementary space, and, in comparison with the tensorial degrees of freedom, it couples to matter in a different way. Moreover, as some stabilization mechanism acts exclusively on the scalar degree of freedom, the tensor and scalar fields should be treated as phenomenologically independent quantities. Based on the spectroscopic data of muonic helium, we find constraints for the effective energy scale of the radion as a function of the alpha particle radius. Then, we discuss the implications of these new constraints on the proton radius puzzle.

16.Fractionary Charged Particles Confronting Lepton Flavor Violation and the Muon's Anomalous Magnetic Moment

Authors:Elmer Ramirez Barreto, Alex G. Dias

Abstract: In light of the result published by the Fermilab Muon $(g-2)$ experiment, we investigate a simple model that includes particles of fractional electric charges: a colour-singlet fermion and a scalar with charges $2/3e$ and $1/3e$, respectively. The impact of these particles on the muon anomalous magnetic moment are examined, particularly the restrictions on their Yukawa couplings with the light leptons. Given that lepton flavor violation processes impose stringent constraints on certain scenarios beyond the Standard Model, we asses the one-loop contribution of the new particles to $(g-2)$ in order to identify regions in the parameter space consistent with the Fermilab results and compatible with the current and projected limits on the branching ratio $Br(\mu \rightarrow e \gamma)$. Taking into account the current lower bound for the masses of fractionary charged particles, which is around 634 GeV, we show that the mass of the scalar particle wi