
arXiv daily: High Energy Physics - Phenomenology (hep-ph)
1.Dispersive determination of neutrino mass orderings
Authors:Hsiang-nan Li
Abstract: We argue that the mixing phenomenon of a neutral meson formed by a fictitious massive quark will disappear, if the electroweak symmetry of the Standard Model (SM) is restored at a high energy scale. This disappearance is taken as the high-energy input for the dispersion relation, which must be obeyed by the width difference between two meson mass eigenstates. The solution to the dispersion relation at low energy, i.e., in the symmetry broken phase, then connects the Cabibbo-Kobayashi-Maskawa (CKM) matrix elements to the quark masses involved in the box diagrams responsible for meson mixing. It is demonstrated via the analysis of the $D$ meson mixing that the typical $d$, $s$ and $b$ quark masses demand the CKM matrix elements in agreement with measured values. In particular, the known numerical relation $V_{us}\approx \sqrt{m_s/m_b}$ with the $s$ ($b$) quark mass $m_s$ ($m_b$) can be derived analytically from our solution. Next we apply the same formalism to the mixing of the $\mu^- e^+$ and $\mu^+ e^-$ states through similar box diagrams with intermediate neutrino channels. It is shown that the neutrino masses in the normal hierarchy (NH), instead of in the inverted hierarchy or quasi-degenerate spectrum, match the observed Pontecorvo-Maki-Nakagawa-Sakata matrix elements. The lepton mixing angles larger than the quark ones are explained by means of the inequality $m_2^2/m_3^2\gg m_s^2/m_b^2$, $m_{2,3}$ being the neutrino masses in the NH. At last, the solution for the $\tau^-e^+$-$\tau^+e^-$ mixing specifies the mixing angle $\theta_{23}\approx 45^\circ$ with slight preference for the first octant. Our work suggests that the fermion masses and mixing parameters are constrained dynamically, and the neutrino mass orderings can be discriminated by the internal consistency of the SM.
2.Belle II observation prospects for axion-like particle production from $B$ meson annihilation decay
Authors:Yi Zhang, Akimasa Ishikawa, Emi Kou, Daniel Thomas Marcantonio, Phillip Urquijo
Abstract: We investigate a new production mechanism of axion-like particle (ALP) from $B$ meson annihilation decays and its observation potential at the Belle and Belle II experiments. This mechanism allows for the production of ALP from $B$ meson decays in association with a large variety of mesons. In this article, we first estimate the branching ratios of such processes with a perturbative QCD method. Focussing on the most promising $B \to h a^{\prime}$ ($h=K^\pm, \pi^\pm, D^0$ and $D_s$) channels, we perform sensitivity studies for $a^{\prime}$ decaying invisibly or into diphoton with Belle and Belle II experiments.
3.Effect of magnetic field on the optical and thermodynamic properties of a high-temperature hadron resonance gas with van der Waals interactions
Authors:Bhagyarathi Sahoo, Kshitish Kumar Pradhan, Dushmanta Sahu, Raghunath Sahoo
Abstract: We study the behavior of a hadronic matter in the presence of an external magnetic field within the van der Waals hadron resonance gas (VDWHRG) model, considering both attractive and repulsive interactions among the hadrons. Various thermodynamic quantities like pressure ($P$), energy density ($\varepsilon$), magnetization ($\mathcal{M}$), entropy density ($s$), squared speed of sound ($c_{\rm s}^{2}$), specific heat capacity at constant volume ($c_{v}$) are calculated as functions of temperature ($T$) and static finite magnetic field ($eB$). We also consider the effect of baryochemical potential ($\mu_{B}$) on the above-mentioned thermodynamic observables in the presence of a magnetic field. Further, we estimate the magnetic susceptibility ($\chi_{\rm M}^{2}$), relative permeability ($\mu_{\rm r}$), and electrical susceptibility ($\chi_{\rm Q}^{2}$) which can help us to understand the system better. With the information of $\mu_{\rm r}$ and dielectric constant ($\epsilon_{r}$), we enumerate the refractive index ($RI$) of the system under consideration. Through this model, we quantify a liquid-gas phase transition in the T-eB-$\mu_B$ phase space.
4.Multiplicity and Transverse Spherocity dependence of $\langle p_{\rm T} \rangle$ fluctuations of charged particles in p$-$p collisions at $\sqrt{s}$ = 7 and 13 TeV
Authors:Subhadeep Roy, Tulika Tripathy, Sadhana Dash
Abstract: The multiplicity dependence of event-by-event fluctuations in mean transverse momentum, $\langle p_{\rm T} \rangle$, of charged particles has been studied in p$-$p collisions at $\sqrt{s}$ = 7 TeV and 13 TeV using the PYTHIA 8 event generator. The charged particles were selected in kinematic range of $0.15 < p_{\rm T}<2$ GeV$/c$ and $|\eta| < 0.8$. The dynamical fluctuations would indicate towards the correlated emission of particles. The measurements in A$-$A and p$-$p collisions has shown a decrease in the strength of $ \langle p_{\rm T} \rangle$ fluctuations with the average charged particle multiplicity. The effects of various microscopic processes like color reconnection and multi-partonic interactions has been studied. A minimal dependency on the collision energy is also observed. Furthermore, the fluctuation observables are investigated in the intervals of transverse spherocity in order to comprehend the relative contributions resulting from hard scattering and underlying events. The present study would act as a baseline for future measurements in A$-$A as well as p$-$p collisions at the LHC.
5.Quark model with Hidden Local Symmetry and its application to $T_{cc}$
Authors:Bing-Ran He, Masayasu Harada, Bing-Song Zou
Abstract: We propose a chiral quark model including the $\omega$ and $\rho$ meson contributions in addition to the $\pi$ and $\sigma$ meson contributions. We show that the masses of the ground state baryons such as the nucleon, $\Lambda_c$ and $\Lambda_b$ are dramatically improved in the model with the vector mesons compared with the one without them. The study of the tetraquark $T_{cc}$ is also performed in a coupled channel calculation and the resultant mass is much closer to the experiment than the result without vector meson contribution. This approach could be applied in future study of multi-quark systems.
6.On the approaches to threshold resummation of rapidity distributions for the Drell-Yan process
Authors:Marco Bonvini, Giulia Marinelli
Abstract: We consider threshold resummation of rapidity distributions, for which various approaches exist in the literature. Recently, a work by Lustermans, Michel, Tackmann suggested that older approaches by Becher, Neubert, Xu (BNX) and Bonvini, Forte, Ridolfi (BFR) were wrong because they miss some leading-power contributions at threshold. In this work, we prove and demonstrate that the BNX and BFR approaches are correct and able to resum threshold logarithms to leading-power accuracy. We then show that the BNX and BFR approaches can provide rather good alternatives to more modern approaches to threshold resummation of rapidity distributions, provided the threshold logarithms are resummed according to the $\psi$-soft definition introduced in the context of Higgs production.
7.Electric dipole moments of charm baryons using dimension-six operators
Authors:Y. Ünal
Abstract: We investigate the $C\!P$-odd electric dipole moments (EDMs) of spin-1/2 charm baryons considering $C\!P$-violating dimension-6 operators in the Standard Model effective field theory. In the framework of heavy-baryon chiral perturbation theory, we calculate the EDMs of single-charm baryons and present the estimates for beyond-the-standard model physics appearing at the TeV scale.
8.Probing anomalous $γγγγ$ couplings at a future muon collider
Authors:H. Amarkhail, S. C İnan, A. V. Kisselev
Abstract: We have studied anomalous four-photon couplings in the $\mu^+\mu^- \rightarrow \mu^+ \gamma\gamma \mu^-$ scattering at a future muon collider, assuming that anomalous quartic gauge couplings with one or two $Z$ bosons are zero. The collision energies of 3 TeV, 14 TeV, and 100 TeV are addressed. Both differential and total cross sections versus invariant mass of the outgoing photons are calculated. The best 95\% C.L. exclusion bounds on anomalous couplings are obtained to be $g_1 = 2.23 \times 10^{-8}$ TeV$^{-4}$ and $g_2 = 4.22 \times 10^{-8}$ TeV$^{-4}$. They correspond to the muon collision energy of 100 TeV. The partial-wave unitary constraints on $g_1$ and $g_2$ are examined. We have demonstrated that the unitarity is not violated in a region of the anomalous couplings obtained in the present paper.
9.Probing the Dark Dimension with Auger data
Authors:Neena T. Noble, Jorge F. Soriano, Luis A. Anchordoqui
Abstract: [Abridged] By combining swampland conjectures with observational data, it was recently noted that our universe could stretch off in an asymptotic region of the string landscape of vacua. In this framework, the cosmological hierarchy problem can be resolved by the addition of one mesoscopic (dark) dimension of size $\sim \lambda \, \Lambda^{-1/4} \sim 1~\mu{\rm m}$. The Planck scale of the higher dimensional theory, $M_{\rm UV} \sim \lambda^{-1/3} \Lambda^{1/12} M_{\rm Pl}^{2/3} \sim 10^{10}~{\rm GeV}$, is tantalizingly close to the energy above which the TA and Auger collaborations found conclusive evidence for a sharp cutoff of the flux of UHECRs. It was recently suggested that since physics becomes strongly coupled to gravity beyond $M_{\rm UV}$, universal features deep-rooted in the dark dimension could control the energy cutoff of the source spectra. Conversely, in the absence of phenomena inborn within the dark dimension, we would expect a high variance of the cosmic ray maximum energy characterizing the source spectra, reflecting the many different properties inherent to the most commonly assumed UHECR accelerators. A recent analysis of Auger and TA data exposed strong evidence for a correlation between UHECRs and nearby starburst galaxies, with a global significance post-trial of $4.7\sigma$. Since these galaxies are in our cosmic backyard, the flux attenuation factor due to cosmic ray interactions en route to Earth turns out to be negligible. This implies that for each source, the shape of the observed spectrum should roughly match the emission spectrum, providing a unique testing ground for the dark dimension hypothesis. Using Auger data, we carry out a maximum likelihood analysis to characterize the shape of the UHECR emission from the galaxies dominating the anisotropy signal. We show that the observed spectra could be universal only if $\lambda \lesssim 10^{-3}$.
10.Potential of the Julia programming language for high energy physics computing
Authors:J. Eschle, T. Gal, M. Giordano, P. Gras, B. Hegner, L. Heinrich, U. Hernandez Acosta, S. Kluth, J. Ling, P. Mato, M. Mikhasenko, A. Moreno Briceño, J. Pivarski, K. Samaras-Tsakiris, O. Schulz, G. . A. Stewart, J. Strube, V. Vassilev
Abstract: Research in high energy physics (HEP) requires huge amounts of computing and storage, putting strong constraints on the code speed and resource usage. To meet these requirements, a compiled high-performance language is typically used; while for physicists, who focus on the application when developing the code, better research productivity pleads for a high-level programming language. A popular approach consists of combining Python, used for the high-level interface, and C++, used for the computing intensive part of the code. A more convenient and efficient approach would be to use a language that provides both high-level programming and high-performance. The Julia programming language, developed at MIT especially to allow the use of a single language in research activities, has followed this path. In this paper the applicability of using the Julia language for HEP research is explored, covering the different aspects that are important for HEP code development: runtime performance, handling of large projects, interface with legacy code, distributed computing, training, and ease of programming. The study shows that the HEP community would benefit from a large scale adoption of this programming language. The HEP-specific foundation libraries that would need to be consolidated are identified
11.Measuring Hadronic Higgs Boson Branching Ratios at Future Lepton Colliders
Authors:Max Knobbe, Frank Krauss, Daniel Reichelt, Steffen Schumann
Abstract: We present a novel strategy for the simultaneous measurement of Higgs-boson branching ratios into gluons and light quarks at a future lepton collider operating in the Higgs-factory mode. Our method is based on template fits to global event-shape observables, and in particular fractional energy correlations, thereby exploiting differences in the QCD radiation patterns of quarks and gluons. In a constrained fit of the deviations of the light-flavour hadronic Higgs-boson branching ratios from their Standard Model expectations, based on an integrated luminosity of $5\,\text{ab}^{-1}$, we obtain $68\%$ confidence level limits of $\mu_{gg}=1 \pm 0.08$ and $\mu_{q\bar{q}}<2.3$.
12.A Scotogenic explanation for the 95 GeV excesses
Authors:Pablo Escribano, Victor Martin Lozano, Avelino Vicente
Abstract: Several hints of the presence of a new state at about $95$ GeV have been observed recently. The CMS and ATLAS collaborations have reported excesses in the diphoton channel at about this diphoton invariant mass with local statistical significances of $2.9 \, \sigma$ and $1.7 \,\sigma$, respectively. Furthermore, a $2 \, \sigma$ excess in the $b\bar{b}$ final state was also observed at LEP, again pointing at a similar mass value. We interpret these intriguing hints of new physics in a variant of the Scotogenic model, an economical scenario that induces Majorana neutrino masses at the loop level and includes a viable dark matter candidate. We show that our model can naturally explain the 95 GeV excesses while respecting all experimental constraints and discuss other phenomenological predictions of our scenario.
13.Photon radiation by relatively slowly rotating fermions in magnetic field
Authors:Matteo Buzzegoli, Jonathan D. Kroth, Kirill Tuchin, Nandagopal Vijayakumar
Abstract: We study the electromagnetic radiation by a fermion carrying an electric charge $q$ embedded in a medium rotating with constant angular velocity $\bf\Omega$ parallel or anti-parallel to an external constant magnetic field $\bf B$. We assume that the rotation is "relatively slow"; namely, that the angular velocity $\Omega$ is much smaller than the inverse magnetic length $\sqrt{qB}$. In practice, such angular velocity can be extremely high. The fermion motion is a superposition of two circular motions: one due to its rigid rotation caused by forces exerted by the medium, another due to the external magnetic field. We derive an exact analytical expression for the spectral rate and the total intensity of this type of synchrotron radiation. Our numerical calculations indicate very high sensitivity of the radiation to the angular velocity of rotation. We show that the radiation intensity is strongly enhanced if $q\bf B$ and $\bf \Omega$ point in the same direction and is suppressed otherwise.
14.The 95.4 GeV di-photon excess at ATLAS and CMS
Authors:T. Biekötter, S. Heinemeyer, G. Weiglein
Abstract: The ATLAS collaboration has recently reported the results of a low-mass Higgs-boson search in the di-photon final state based on the full Run 2 data set. The results are based on an improved analysis w.r.t. the previous analysis, which included a part of the Run 2 data, with a substantially better sensitivity. The ``model-dependent'' search carried out by ATLAS shows an excess of events at a mass of about 95.4 GeV with a local significance of $1.7\,\sigma$. The results are compatible with a previously reported excess at the same mass, but somewhat higher significance of $2.9\,\sigma$, from the CMS collaboration, also based on the full Run 2 data set. Combining the two results (neglecting possible correlations) we find a signal strength of $\mu_{\gamma\gamma}^{\rm ATLAS+CMS} = 0.27^{+0.10}_{-0.09}$, corresponding to an excess of $3.2\,\sigma$. In this work, we investigate the implications of this result, updating a previous analysis based solely on the CMS Run 2 data. We demonstrate that the ATLAS/CMS combined di-photon excess can be interpreted as the lightest Higgs boson in a Two-Higgs doublet model that is extended by a complex singlet (S2HDM) of Yukawa types II and IV, while being in agreement with all other experimental and theoretical constraints.
15.Critical Points in Palatini Higgs Inflation with Small Non-Minimal Coupling
Authors:Arthur Poisson, Inar Timiryasov, Sebastian Zell
Abstract: We investigate inflation driven by the Higgs boson in the Palatini formulation of General Relativity. Our analysis primarily focuses on a small non-minimal coupling of the Higgs field to gravity in the range $0<\xi\lesssim 1$. We incorporate the renormalization group running of the relevant parameters as computed within the Standard Model and allow for small corrections. In addition to $\xi$, our model features two tunable parameters: the low-energy value of the top Yukawa coupling and an effective jump of the Higgs self-interaction. Our results indicate that critical points leading to a large enhancement of the power spectrum can be produced. However, the observed amplitude of perturbations in the CMB cannot be matched within this setting. On the one hand, this makes it difficult to generate a sizable abundance of primordial black holes. On the other hand, our finding can be viewed as further evidence that Palatini Higgs inflation has favourable high-energy properties due to robustness against quantum corrections.
1.The transverse momentum distribution of J/ψ mesons produced in pp collisions at the LHC
Authors:Li-Na Gao, Er-Qin Wang
Abstract: The transverse momentum distributions of J/{\psi}mesons produced in pp collisions at the center-of-mass energy 5 TeV, 7TeV, and 13 TeV are described by the modified Hagedorn function. The fitting results by the modified Hagedorn function are in accord with experimental data measured by the LHCb Collaboration at LHC. The related parameters are obtained and analyzed.
2.Dynamically-assisted nonlinear Breit-Wheeler pair production in bichromatic laser fields of circular polarization
Authors:N. Mahlin, S. Villalba-Chávez, C. Müller
Abstract: Production of electron-positron pairs by a high-energy $\gamma$ photon and a bichromatic laser wave is considered where the latter is composed of a strong low-frequency and a weak high-frequency component, both with circular polarization. An integral expression for the production rate is derived that accounts for the strong laser mode to all orders and for the weak laser mode to first order. The structure of this formula resembles the well-known expression for the nonlinear Breit-Wheeler process in a strong laser field, but includes the dynamical assistance from the weak laser mode. We analyze the dependence of the dynamical rate enhancement on the applied field parameters and show, in particular, that it is substantially higher when the two laser modes have opposite helicity.
3.On the decay mode $Λ_b \to X_s γ$
Authors:P. Colangelo, F. De Fazio, F. Loparco
Abstract: We study the inclusive $H_b \to X_s \gamma$ decay with $H_b$ a beauty baryon, in particular $\Lambda_b$, employing an expansion in the heavy quark mass at $\mathit{O}(m_b^{-3})$ at leading order in $\alpha_s$, keeping the dependence on the hadron spin. For a polarized baryon we compute the distribution $\displaystyle\frac{d^2\Gamma}{dy \, d \cos \theta_P}$, with $y=2E_\gamma/m_b$, $E_\gamma$ the photon energy and $\theta_P$ the angle between the baryon spin vector and the photon momentum in the $H_b$ rest-frame. We discuss the correlation between the baryon and photon polarization, and show that effects of physics beyond the Standard Model can modify the photon polarization asymmetry. We also discuss a method to treat the singular terms in the photon energy spectrum obtained by the OPE.
4.Novel approach to investigate $η$ decays via $η'\rightarrowππη$
Authors:Xiaolin Kang, Yuyao Ji, Xiaoqing Yuan, Benhou Xiang, Xiaorong Zhou, Haiping Peng, Xingtao Huang, Shuangshi Fang
Abstract: To avoid the impact from the background events directly from $e^+e^-$ annihilations or $J/\psi$ decays, we propose a novel approach to investigate $\eta$ decays, in particular for its rare or forbidden decays, by using $\eta^\prime\rightarrow\pi\pi\eta$ produced in $J/\psi$ decays at the $\tau-$charm factories. Based on the MC studies of a few typical decays, $\eta\rightarrow \pi\pi$, $\gamma l^+l^- (l= e, \mu)$, $l^+l^-$, as well as $l^+l^-\pi^0$, the sensitivities could be obviously improved by taking advantage of the extra constraint of $\eta^\prime$. Using one trillion $J/\psi$ events accumulated at the Super $\tau$-Charm facility, the precision on the investigation of $\eta$ decays could be improved significantly and the observation of the rare decay $\eta\rightarrow e^+e^-$ is even accessable.
5.Exploring the linear space of Feynman integrals via generating functions
Authors:Xin Guan, Xiang Li, Yan-Qing Ma
Abstract: Deriving a comprehensive set of reduction rules for Feynman integrals has been a longstanding challenge. In this paper, we present a proposed solution to this problem utilizing generating functions of Feynman integrals. By establishing and solving differential equations of these generating functions, we are able to derive a system of reduction rules that effectively reduce any associated Feynman integrals to their bases. We illustrate this method through various examples and observe its potential value in numerous scenarios.
6.Full treatment of the thrust distribution in single inclusive $e^+ e^- \to h \, X$ processes
Authors:M. Boglione, A. Simonelli
Abstract: Extending the transverse momentum dependent factorization to thrust dependent observables entails a series of difficulties, ultimately associated to the behavior of soft radiation. As a consequence, the definition of the transverse momentum dependent functions has to be revised, while preserving (and possibly extending) their universality properties. Moreover, the regularization of the rapidity divergences generates non trivial correlations between rapidity and thrust. In this paper, we show how to deal with these correlations in a consistent treatment of the thrust dependence of $e^+ e^- \to h \, X$ cross section, where the hadron transverse momentum is measured with respect to the thrust axis. In this framework all results obtained in the past few years properly fit together, leading to a remarkable phenomenological description of the experimental measurements.
7.Heavy Flavoured Meson Fragmentation Functions in $e^+e^-$ annihilation up to NNLO + NNLL
Authors:Leonardo Bonino, Matteo Cacciari, Giovanni Stagnitto
Abstract: In this contribution, we make use of the QCD perturbative fragmentation function formalism to describe the one-particle inclusive fragmentation of a heavy quark produced in $e^+e^-$ annihilation at $\mathcal{O}(\alpha_S^2)$. We perform the computation analytically in Mellin-space. We resum soft-gluons effects in initial conditions and coefficient functions and perform evolution up to NNLL accuracy, obtaining the first NNLO + NNLL prediction for charm quark production. We study the impact of different matching schemes and Landau pole prescriptions in soft-gluon resummation, finding significant differences. We extract simple non-perturbative fragmentation functions for $B$ and $D^*$ mesons by comparing the perturbative prediction with the data from CLEO, BELLE and LEP experiments. We find that for charm mesons the experimental results from CLEO/BELLE and from LEP are not reconcilable with the standard DGLAP evolution.
8.Renormalization Group Equations for the SMEFT Operators up to Dimension Seven
Authors:Di Zhang
Abstract: In this paper, we propose a Green's basis and also a new physical basis for dimension-seven (dim-7) operators, which are suitable for the matching of ultraviolet models onto the Standard Model effective field theory (SMEFT) and the deviation of renormalization group equations (RGEs) for dim-7 operators in the SMEFT. The reduction relations to convert operators in the Green's basis to those in the physical basis are achieved as well, where some redundant dim-6 operators in the Green's basis are involved if the dim-5 operator exists. Working in these two bases for dim-7 operators and with the help of the reduction relations, we work out the one-loop RGEs resulting from the mixing among different dimensional operators for the dim-5 and dim-7 operators up to $\mathcal{O} \left( \Lambda^{-3} \right)$ in the SMEFT. These new results complete the previous results for RGEs of the dim-5 and dim-7 operators and hence can be used for a consistent one-loop analysis of the SMEFT at $\mathcal{O} \left( \Lambda^{-3} \right)$.
9.P, CP solution of the strong CP puzzle
Authors:Ravi Kuchimanchi
Abstract: We use parity (P) to set $\theta_{QCD}$ to zero in the minimal left-right symmetric model, add a heavy vectorlike quark family, and obtain in a novel manner the Nelson Barr (NB) form associated so far only with spontaneous CP solution to the strong CP Puzzle. Our solution does not have the `coincidence of scales problem', that typically plagues NB models. P protects $\bar{\theta}$, if it breaks at a scale $v_R$ below the mass $M$ of the heavy quarks, and $\bar{\theta} \sim 10^{-9} (v_R/M)^2$ is radiatively generated, which can be acceptably small. On the other hand, if $M < v_R$, the $\bar{\theta} \sim 10^{-9}$ generated by the NB mechanism is too large, but $\delta_{CKM}$ can be obtained without the NB mechanism, and surprisingly a lower irreducible $\bar{\theta} \sim (10^{-13}~to~10^{-10}) ln( {v_R/M)}$, testable by neutron EDM experiments is generated. No leptonic CP violation is generated (Dirac phase $\delta_{CP} = 0~or~\pi$ in PMNS matrix) which makes the minimal model testable by neutrino experiments. We also discuss some challenges in a non-minimal model that generates leptonic CP violation. Lastly but importantly, we find with $SU(2)_L \times SU(2)_R$ gauge group, that there is an \textit{automatic} NB solution on imposing CP (global symmetry usually imposed to get the NB form is accidental once we have $SU(2)_R$), which does not require mirror or generalized parity and is more economical, as it works also with just 1 mirror generation.
1.Flavor structure from `canonical' Yukawa interactions and `emergent' kinetic terms
Authors:Yoshiharu Kawamura
Abstract: We study the flavor structure of quarks in the standard model from a viewpoint of a canonical type of Yukawa interactions and an emergence of kinetic terms. A realistic structure can be generated based on the emergence proposal that quark kinetic terms appear in the infra-red region, as a result of radiative corrections involving towers of massive states.
2.Higgs Information and NMSSM at the Large Hadron Collider
Authors:Surabhi Gupta, Sudhir Kumar Gupta
Abstract: Information theory has proven to be a worthwhile tool for investigating the implications of the Higgs sector in the Next-to-minimal supersymmetric Standard Model (NMSSM) using Higgs information at the Large Hadron Collider assessed through the entropy constructed by means of the branching ratios of decay channels of the Higgs boson. The present article focuses on the parameter space of supersymmetric extension with an extra term of gauge singlet in light of various experimental constraints. Our findings show the most preferred values of $m_0$, $m_{1/2}$, $ A_0$, $ tan\beta$, $\lambda$, $\mu_{eff}$, neutralino LSP $ m_{\tilde\chi^{0}_{1}}$, lightest chargino $ m_{\tilde\chi^{\pm}_{1}}$, singlino $ m_{\tilde\chi^{0}_{5}}$, and gluino $ m_{\tilde g}$ to be around 1.93 TeV, 1.78 TeV, $-$3.62 TeV, 27.5, 0.012, 665.7 GeV, 0.74 TeV, 0.79 TeV, 11.24 TeV, and 3.70 TeV, respectively, that is compatible with the relic density of dark matter.
3.Cosmological Phase Transitions in Composite Higgs Models
Authors:Kohei Fujikura, Yuichiro Nakai, Ryosuke Sato, Yaoduo Wang
Abstract: We investigate cosmological phase transitions in various composite Higgs models consisting of four-dimensional asymptotically-free gauge field theories. Each model may lead to a confinement-deconfinement transition and a phase transition associated with the spontaneous breaking of a global symmetry that realizes the Standard Model Higgs field as a pseudo-Nambu-Goldstone boson. Based on the argument of universality, we discuss the order of the phase transition associated with the global symmetry breaking by studying the renormalization group flow of the corresponding linear sigma model at finite temperature, which is calculated by utilizing the $\epsilon$-expansion technique at the one-loop order. Our analysis indicates that some composite Higgs models accommodate phenomenologically interesting first-order phase transitions. We also explore the confinement-deconfinement transition in a UV-completed composite Higgs model based on a $Sp(2N_c)$ gauge theory. It is found that the first-order phase transition is favored when the number of degrees of freedom for the $Sp(2N_c)$ gauge field is much larger than that of matter fields in the fundamental representation of $Sp(2N_c)$. We comment on the gravitational wave signal generated by the confinement-deconfinement transition and its detectability at future observations. Our discussions motivate further studies on phase transitions in composite Higgs models with the use of lattice simulations.
4.Deep-Inelastic Scattering: What do we know ?
Authors:Johannes Blümlein
Abstract: A survey is given on the current status of the theoretical description of unpolarized and polarized deep--inelastic scattering processes in Quantum Chromodynamics at large virtualities.
5.Combined analysis of the $γn \to K^0Σ^0$ and $γn \to K^+Σ^-$ reactions
Authors:Neng-Chang Wei, Ai-Chao Wang, Fei Huang
Abstract: The recently released data on differential cross sections for $\gamma n \to K^0\Sigma^0$ from the A2 and BGOOD Collaborations are used to examine the theoretical model constructed in our previous work [Phys. Rev. D \textbf{105}, 094017 (2022)] for $\gamma n \to K^+\Sigma^-$, and it is found that the model predictions are able to qualitatively reproduce the A2 data but fail to describe the BGOOD data. Then, a combined analysis of the $\gamma n \to K^0\Sigma^0$ and $\gamma n \to K^+\Sigma^-$ reactions is performed to revise the theoretical model. Due to the inconsistency problem, the A2 and BGOOD data are included in fits separately. In the case of including the A2 data, both the data for $\gamma n \to K^0\Sigma^0$ and $\gamma n \to K^+\Sigma^-$ can be fairly well described, and the contributions from the $N(1710)1/2^+$, $N(1880)1/2^+$, $N(1900)3/2^+$, and $\Delta(1920)3/2^+$ resonances are found to dominate the reactions in the lower energy region. While in the case of including the BGOOD data, although most of the data for the $\gamma n \to K^+ \Sigma^-$ reaction can be described with the exception of some noticeable discrepancies on beam asymmetries at lower energies, the BGOOD data for $\gamma n \to K^0\Sigma^0$ can be only qualitatively described, and the contributions from the $N(1710)1/2^+$, $N(1900)3/2^+$, and $\Delta(1910)1/2^+$ resonances are found to dominate the reactions in the lower energy region. In both cases, the $t$-channel $K^\ast(892)$ exchange is found to play a crucial role at forward angles in the higher energy region. Further precise measurements of data for $\gamma n \to K^0\Sigma^0$ are called on to disentangle the discrepancies between the data sets from the A2 and BGOOD Collaborations.
6.Dark Matter from Higher Dimensional Primordial Black Holes
Authors:Avi Friedlander, Ningqiang Song, Aaron C. Vincent
Abstract: The evaporation of primordial black holes provides a promising dark matter production mechanism without relying on any non-gravitational interactions between the dark sector and the Standard Model. In theories of ``Large'' Extra Dimensions (LEDs), the true scale of quantum gravity, $M_*$, could be well below the Planck scale, thus allowing for energetic particle collisions to produce microscopic black holes in the primordial plasma at temperatures as low as $T \gtrsim 100$ GeV. Additionally, LEDs modify the relationship between black hole mass, radius, and temperature, allowing microscopic black holes to grow to macroscopic sizes in the early Universe. In this work we study three scenarios for the production of dark matter via LED black holes: 1) Delayed Evaporating Black Holes (DEBHs) which grow to macroscopic sizes before ultimately evaporating, 2) Instantly Evaporating Black Holes (IEBHs) which immediately evaporate, and 3) stable black hole relics with a mass $M_*$ known as Planckeons. For a given reheating temperature, $T_\mathrm{RH}$, we show that DEBHs produce significantly less dark matter than both IEBHs and Planckeons. IEBHs are able to produce the observed relic abundance of dark matter so long as the reheating scale is in the range $10^{-2} \leq T_\mathrm{RH}/M_* \leq 10^{-1}$. We calculate the average speed for the resulting dark matter and show that it would be sufficiently cold for all dark matter masses $m_{dm} \gtrsim 10^{-4}$ GeV. This mechanism is viable for any scale of quantum gravity in the range $10^4\,\mathrm{ GeV} \leq M_* \leq M_{Pl}$ and for any number of LEDs.
7.Forward Neutrinos from Charm at Large Hadron Collider
Authors:Atri Bhattacharya, Felix Kling, Ina Sarcevic, Anna M. Stasto
Abstract: The currently operating FASER experiment and the planned Forward Physics Facility (FPF) will detect a large number of neutrinos produced in proton-proton collisions at the LHC. In addition to neutrinos from pion and kaon decays, a significant contribution is expected from the decay of charmed hadrons, particularly for electron and tau neutrino flavors. In this work, we investigate two QCD formulations for the production of charm quarks in $pp$ collisions: the next-to-leading order collinear factorization and the $k_T$-factorization approach. We use state of the art fragmentation schemes to obtain hadron cross-sections and validate them against corresponding LHCb data. These calculations are then used to predict the forward neutrino flux from charm hadron decays. We further scrutinize the impact of varying QCD parameters, such as scales, the selection of parton distribution functions, and the modeling of fragmentation, on these predictions. We find that the measurement of forward neutrino flux will serve as a complementary tool to probe QCD dynamics and will offer valuable insights for astroparticle physics.
8.Evolution of genuine states to molecular ones: The $T_{cc}(3875)$ case
Authors:L. R. Dai, J. Song, E. Oset
Abstract: We address the issue of the compositeness of hadronic states and demonstrate that starting with a genuine state of nonmolecular nature, but which couples to some meson-meson component to be observable in that channel, if that state is blamed for a bound state appearing below the meson-meson threshold it gets dressed with a meson cloud and it becomes pure molecular in the limit case of zero binding. We discuss the issue of the scales, and see that if the genuine state has a mass very close to threshold, the theorem holds, but the molecular probability goes to unity in a very narrow range of energies close to threshold. The conclusion is that the value of the binding does not determine the compositeness of a state. However, in such extreme cases we see that the scattering length gets progressively smaller and the effective range grows indefinitely. In other words, the binding energy does not determine the compositeness of a state, but the additional information of the scattering length and effective range can provide an answer. We also show that the consideration of a direct attractive interaction between the mesons in addition to having a genuine component, increases the compositeness of the state. Explicit calculations are done for the $T_{cc}(3875)$ state, but are easily generalized to any hadronic system.
9.Combining lattice QCD and phenomenological inputs on generalised parton distributions at moderate skewness
Authors:Michael Joseph Riberdy, Hervé Dutrieux, Cédric Mezrag, Paweł Sznajder
Abstract: We present a systematic study demonstrating the impact of lattice QCD data on the extraction of generalised parton distributions (GPDs). For this purpose, we use a previously developed modelling of GPDs based on machine learning techniques fulfilling the theoretical requirements of polynomiality, a form of positivity constraint and known reduction limits. A special care is given to estimate the uncertainty stemming from the ill-posed character of the connection between GPDs and the experimental processes usually considered to constrain them, like deeply virtual Compton scattering (DVCS). Mock lattice QCD data inputs are included in a Bayesian framework to the prior model which is fitted to reproduce the most experimentally accessible information of a phenomenological model by Goloskov and Kroll. We highlight the impact of the precision, correlation and kinematic coverage of lattice data on GPD extraction at moderate $\xi$ which has only been brushed in the literature so far, paving the way for a joint extraction of GPDs.
10.Helicity Evolution at Small $x$: Revised Asymptotic Results at Large $N_c\& N_f$
Authors:Daniel Adamiak, Yuri V. Kovchegov, Yossathorn Tawabutr
Abstract: We present a numerical solution of the revised version of the small-$x$ helicity evolution equations at large $N_c$ and $N_f$. (Here $N_c$ and $N_f$ are the numbers of quark colors and flavors, respectively.) The evolution equations are double-logarithmic in the Bjorken $x$ variable, resumming powers of $\alpha_s \, \ln^2 (1/x)$ with $\alpha_s$ the strong coupling constant. The large-$N_c \& N_f$ evolution we consider includes contributions of small-$x$ quark emissions and is thus more realistic than the large-$N_c$ one, which only involves gluon emissons. The evolution equations are written for the so-called ``polarized dipole amplitudes", which are related to the helicity distribution functions and the $g_1$ structure function. Unlike the previously reported solution of the earlier version of helicity evolution equations at large $N_c \& N_f$, our solution does not exhibit periodic oscillations in $\ln (1/x)$ for $N_f < 2 N_c$, while only showing occasional sign reversals. For $N_f = 2 N_c$, we report oscillations with $\ln (1/x)$, similar to those found earlier. We determine the intercept of our evolution for $N_f < 2 N_c$ as well as the parameters of the oscillatory behavior for $N_f = 2 N_c$. We compare our results to the existing resummation and finite-order calculations for helicity-dependent quantities in the literature.
1.Dynamical Inflation Stimulated Cogenesis
Authors:Debasish Borah, Arnab Dasgupta, Daniel Stolarski
Abstract: We propose a minimal setup that realises dynamical inflection point inflation, and, using the same field content, generates neutrino masses, a baryon asymmetry of the universe, and dark matter. A dark $SU(2)_D$ gauge sector with a dark scalar doublet playing the role of inflaton is considered along with several doublet and singlet fermions sufficient to realise multiple inflection points in the inflaton potential. The singlet fermions couple to SM leptons and generate neutrino masses via the inverse seesaw mechanism. Those fermions also decay asymmetrically and out of equilibrium, generating a baryon asymmetry via leptogenesis. Some of the fermion doublets are dark matter, and they are produced via freeze-in annihilation of the same fermions that generate the lepton asymmetry. Reheating, leptogenesis, and dark matter are all at the TeV scale.
2.Melting of Quarkonia in strong magnetic field
Authors:Manohar Lal, Siddhartha Solanki, Rishabh Sharma, Vineet Kumar Agotiya
Abstract: In this paper, spectra of the quarkonium states has been studied using the conditions temperature, chemical potential and the magnetic field. Here our main focus is to study the effect of strong magnetic field on the quarkonium properties. The binding energies and the dissociation temperature for the ground and the first excited states of the charmonium and bottomonium in the presence of strong magnetic field at chemical potential \mu = 500 MeV has been studied. Here we use quasiparticle (QP) Debye mass depending upon temperature, magnetic field and chemical potential obtained from the quasiparticle approach. The Debye mass strongly increases at different values of temperature and magnetic field. The binding energy decreases with increase in the temperature at different magnetic field eB= 0.3, 0.5, and 0.7 GeV2 and also decreases with magnetic field at different at T=200,300 and 400 MeV for the J/\psi, \psi, \upsilon, and \upsilon prime states of the quarkonia. The dissociation temperature of the quarkonium states falls with the increasing values of the magnetic field at critical temperature Tc =197 MeV
3.Chiral Transport Phenomena and Compact Stars
Authors:Cristina Manuel
Abstract: I will review the main chiral transport phemomena arising in systems made up of (almost) massless fermions associated to the quantum chiral anomaly. These quantum effects might have relevant implications in compact stars, and I will review some relevant works that reveal so. I will also show how a conservation law that has the same form of the chiral anomaly also emerge in perfect classical fluids, which expresses a conservation law of magnetic, fluid and mixed helicities for isentropic fluids, and why this should also be relevant in compact stars.
4.Super Restoration of Chiral Symmetry in Massive Four-Fermion Interaction Models
Authors:Tomohiro Inagaki, Daiji Kimura, Hiromu Shimoji
Abstract: The chiral symmetry is explicitly and spontaneously broken in a strongly interacting massive fermionic system. We study the chiral symmetry restoration in massive four-fermion interaction models with increasing temperature and chemical potential. At high temperature and large chemical potential, we find the boundaries where the spontaneously broken chiral symmetry can be fully restored in the massive Gross--Neveu model. We call the phenomenon super restoration. The phase boundary is obtained analytically and numerically. In the massive Nambu--Jona-Lasinio model, it was found that whether super restoration occurs depends on regularizations. We also evaluate the behavior of the dynamical mass and show the super restoration boundaries on the ordinary phase diagrams.
5.Exploring the dark sectors via the cooling of white dwarfs
Authors:Jaime Hoefken Zink, Maura E. Ramirez-Quezada
Abstract: As dense and hot bodies with a well-understood equation of state, white dwarfs offer a unique opportunity to investigate new physics. In this paper, we examine the role of dark sectors, which are extensions of the Standard Model of particle physics that are not directly observable, in the cooling process of white dwarfs. Specifically, we examine the role of a dark photon, within the framework of a three-portal Model, in enhancing the neutrino emission during the cooling process of white dwarfs. We compare this scenario to the energy release predicted by the Standard Model. By analyzing the parameter space of dark sectors, our study aims to identify regions that could lead to significant deviations from the expected energy release of white dwarfs.
6.Elastic pion-proton and pion-pion scattering via the holographic Pomeron and Reggeon exchange
Authors:Zhibo Liu, Akira Watanabe
Abstract: The elastic pion-proton and pion-pion scattering are studied in a holographic QCD model, focusing on the Regge regime. Taking into account the Pomeron and Reggeon exchange, which are described by the Reggeized $2^{++}$ glueball and vector meson propagator respectively, the total and differential cross sections are calculated. The adjustable parameters involved in the model are determined with the experimental data of the pion-proton total cross sections. The differential cross sections can be predicted without any additional parameters, and it is shown that our predictions are consistent with the data. The energy dependence of the Pomeron and Reggeon contribution is also discussed.
7.Associated Production of Fermionic Dark Matter and Neutrino at the Future Lepton Colliders
Authors:Shao-Feng Ge, Kai Ma, Xiao-Dong Ma, Jie Sheng
Abstract: In light of the fermionic dark matter absorption on electron target that can be observed by direct detection experiments, we study its complementary searches at the future $e^+ e^-$ colliders such as CEPC, FCC-ee, ILC, and CLIC. Two typical processes, the mono-photon and electron-positron pair production associated with missing energy, can serve the purpose. While the mono-photon search prevails at CEPC, FCC-ee, and ILC, the $e^+ e^-E_{T}^{\rm miss}$ channel has more significant contributions at CLIC with much higher collision energy $\sqrt s$. The beam polarizations can help further suppressing the SM backgrounds to enhance the signal significance while differential cross sections can distinguish the Lorentz structure of various effective operators. The combined sensitivity can reach well above 1 TeV at CEPC/FCC-ee and ILC while it further touches 30 TeV at CLIC. Comparing with the updated results from the dark matter direct detection experiments (XENON1T, PandaX-II, PandaX-4T, LZ, and XENONnT), astrophysical $X/\gamma$ observations, and cosmological constraints, the collider searches can not just provide better sensitivity for light dark matter mass but also scan much wider mass range.
8.Gluon condensation, entanglement entropy and phase transition from holography
Authors:Bo Yu, Peng-Cheng Chu, Xiao-Hua Li, Xun Chen
Abstract: We consider the effect of gluon condensation on the holographic entanglement entropy, which can be regarded as an order parameter of deconfinement phase transition, in a holographic model at zero and finite temperature. At zero temperature, it is found that phase transition can occur at critical length for small gluon condensation. With the increase of gluon condensation, the critical length becomes small which means the phase transition is easy to occur. The difference of entanglement entropy between the connected and disconnected surfaces is always negative at large gluon condensation, which indicates no phase transition can occur in the deconfined phase as the subsystem size varies. These results show that the gluon condensation is related to the phase transition and contributes to deconfinement. At finite temperature, we can see that the difference of the entanglement entropy is also always negative and the system is always deconfined for vanishing and non-vanishing gluon condensation in this model. These results confirm that the difference of entanglement entropy is a useful probe to detect whether a system is in the confinement or deconfinement phase.
9.Exclusive $η_c$ production by $γ^{*} γ$ interactions in electron-ion collisions
Authors:Izabela Babiarz, Victor P. Goncalves, Wolfgang Schäfer, Antoni Szczurek
Abstract: One of the main goals of future electron-ion colliders is to improve our understanding of the structure of hadrons. In this letter, we study the exclusive $\eta_c$ production by $\gamma^{*} \gamma$ interactions in $eA$ collisions and demonstrate that future experimental analysis of this process can be used to improve the description of the $\eta_c$ transition form factor. The rapidity, transverse momentum and photon virtuality distributions are estimated considering the energy and target configurations expected to be present at the EIC, EicC and LHeC and assuming different predictions for the light-front wave function of the $\eta_c$ meson. Our results indicate that the electron-ion colliders can be considered an alternative to providing supplementary data to those obtained in $e^- e^+$ colliders.
10.Anisotropic behavior of S-wave and P-wave states of heavy quarkonia at finite magnetic field
Authors:Manohar Lal, Siddhartha Solanki, Rishabh Sharma, Vineet Kumar Agotiya
Abstract: We studied the effect of momentum space anisotropy on heavy quarkonium states using an extended magnetized effective fugacity quasiparticle model (EQPM). Both the real and imaginary part of the potential has been modified through the dielectric function by including the anisotropic parameter $\xi$. The real part of the medium modified potential becomes more attractive in the presence of the anisotropy and constant magnetic field. The binding energy of the 1S, 2S, and 1P quarkonium states including anisotropy effects for both the oblate and the isotropic case were studied. We find that the binding energy of quarkonium states becomes stronger in the presence of anisotropy. However, the magnetic field is found to reduce the binding energy. The thermal width of the charmonium and bottomonium 1S states have been studied at constant magnetic field eB = 0.3 GeV2 for isotropic and prolate cases. The effect of magnetic field on the mass spectra of the 1P state for the oblate case was also examined. The dissociation temperature for the 1S, 2S, and 1P charmonium and bottomonium have been determined to be higher for the oblate case with respect to the isotropic case
11.Introduction to Generalized Global Symmetries in QFT and Particle Physics
Authors:T. Daniel Brennan, Sungwoo Hong
Abstract: Generalized symmetries (also known as categorical symmetries) is a newly developing technique for studying quantum field theories. It has given us new insights into the structure of QFT and many new powerful tools that can be applied to the study of particle phenomenology. In these notes we give an exposition to the topic of generalized/categorical symmetries for high energy phenomenologists although the topics covered may be useful to the broader physics community. Here we describe generalized symmetries without the use of category theory and pay particular attention to the introduction of discrete symmetries and their gauging.
12.Looking forward to photon-coupled long-lived particles IV: neutralino-ALPino/gravitino
Authors:Krzysztof Jodłowski
Abstract: Various supersymmetric (SUSY) scenarios predict a sub-GeV neutralino decaying into a single photon and an invisible state. This signature has recently been studied in a number of intensity frontier experiments, finding constraints complementary to the usual collider searches. In this work, we study the prospects of searches for long-lived neutralinos coupled to an ALPino or gravitino, where each can act as the lightest SUSY particle (LSP). In addition to the neutralino decays into a LSP and a photon, we also consider three-body decays into a pair of charged leptons, and signatures related to scattering with electrons and secondary neutralino production. For both models, we find that the searches at FASER2 will allow to overcome the current bounds, while SHIP will extend these limits by more than an order of magnitude in the value of the coupling constant.
1.Sensitivity of the future $\boldsymbol{e^{-}p}$ collider to the coupling of axion-like particles with vector bosons
Authors:Chong-Xing Yue, Han Wang, Xue-Jia Cheng, Yue-Qi Wang
Abstract: Axion-like particles (ALPs) arise naturally in many extensions of the Standard Model (SM). We explore the discovery potential for ALPs of the Large Hadron electron Collider (LHeC) via the $W^{+}W^{-}$ fusion process. For concreteness, both cases of the ALP decaying to muon pairs and $b\overline{b}$ pairs are investigated. Our numerical results show that the LHeC with the center of mass energy of $1.3$ TeV and the integrated luminosity of $1$ ab$^{-1}$ might be more sensitive than the LHC in probing ALPs over a range of masses from a few tens of GeV to $900$ GeV, where the promising sensitivities to the coupling of ALP with $W^{\pm}$ bosons reach nearly $0.15$ TeV$^{-1}$ and $0.32$ TeV$^{-1}$ for the signal processes $e^{-}p\rightarrow\nu_{e}ja(a\rightarrow\mu^{+}\mu^{-})$ and $e^{-}p\rightarrow\nu_{e}ja(a\rightarrow b\overline{b})$, respectively.
2.Determination of time-dependent electric dipole moments conditioned by axion-photon coupling
Authors:Alexander J. Silenko
Abstract: It is shown that the axion-photon coupling leads to an appearance of time-dependent electric dipole moments of leptons and contributes to electric dipole moments of hadrons. The relation between these moments and the axion-photon coupling constant is rigorously determined. The results obtained open a possibility to compare a sensitivity of search for dark matter axions (and axion-like particles) in optical experiments and experiments with massive particles.
3.2HDM interpretations of the CMS diphoton excess at 95 GeV
Authors:Duarte Azevedo, Thomas Biekötter, P. M. Ferreira
Abstract: In both Run 1 and Run 2 of the LHC, the CMS collaboration has observed an excess of events in the searches for low-mass Higgs bosons in the diphoton final state at a mass of about 95 GeV. After a recent update of the experimental analysis, in which the full Run 2 data collected at 13 TeV has been included and an improved experimental calibration has been applied, the local significance of the excess amounts to $2.9\sigma$. The presence of this diphoton excess is especially interesting in view of a further excess observed by CMS in ditau final states at a comparable mass and similar local significance. Moreover, an excess of events with about $2\sigma$ local significance and consistent with a mass of 95 GeV was observed in LEP searches for a Higgs boson decaying to pairs of bottom quarks. We interpret the CMS diphoton excess in combination with the ditau excess in terms of a pseudoscalar resonance in the CP-conserving two-Higgs-doublet model (2HDM). Furthermore, we discuss the possibility that, if CP-violation is taken into account, a CP-mixed scalar state can in addition describe the LEP result, thus accommodating all three excesses simultaneously. We find that the region of parameter space where both the CMS diphoton and ditau excesses can be fitted is in tension with current constraints from the flavour sector, potentially calling for other new-physics contributions to flavour-physics observables, most notably $b \to s\gamma$ transitions.
4.New Physics in Neutrino Oscillation: Nonunitarity or Nonorthogonality?
Authors:Chee Sheng Fong
Abstract: Neutrino oscillation phenomenon is a definite evidence of physics beyond the Standard Model (SM) and high precision measurement of neutrino properties will certainly give us clue about what lies beyond the SM. In particular, precise measurements of the mixing matrix elements $U_{\alpha i}$ which relate the neutrino flavor $\alpha$ and mass $i$ eigenstates are crucial since new physics at scale beyond experimental reach can lead to a nonunitary $U$. This in turns results in nonorthogonal neutrino flavor states. How to calculate the oscillation probability in this scenario is an important theoretical issue that will be treated here. We show that probability constructed using theory of projection probability will ensure that the theory remains unitary in time evolution and the probabilities of neutrino of certain flavor being detected as all possible flavor states always sum up to unity. This result is crucial for discovery of new physics through neutrino oscillation phenomena.
5.Numerical Scattering Amplitudes with pySecDec
Authors:G. Heinrich, S. P. Jones, M. Kerner, V. Magerya, A. Olsson, J. Schlenk
Abstract: We present a major update of the program pySecDec, a toolbox for the evaluation of dimensionally regulated parameter integrals. The new version enables the evaluation of multi-loop integrals as well as amplitudes in a highly distributed and flexible way, optionally on GPUs. The program has been optimised and runs up to an order of magnitude faster than the previous release. A new integration procedure that utilises construction-free median Quasi-Monte Carlo rules is implemented. The median lattice rules can outperform our previous component-by-component rules by a factor of 5 and remove the limitation on the maximum number of sampling points. The expansion by regions procedures have been extended to support Feynman integrals with numerators, and functions for automatically determining when and how analytic regulators should be introduced are now available. The new features and performance are illustrated with several examples.
6.The next-to-leading BFKL evolution for dijets with large rapidity separation at different LHC energies
Authors:Anatolii Iu. Egorov, Victor T. Kim
Abstract: The calculations based on the next-to-leading logarithm (NLL) approximation for the Balitsky-Fadin-Kuraev-Lipatov (BKFL) evolution are presented for the Mueller-Navelet (MN) dijet production cross section, as well as for their ratios at different collision energies. The MN dijet denotes the jet pair consists of jets, which were selected with $p_{\perp} > p_{\perp\min}$ and with maximal rapidity separation in the event. The NLL BFKL predictions for the MN cross sections are given for the $pp$ collisions at $\sqrt{s}=2.76$, 8 and 13 TeV, for $p_{\perp\min} = 20$ and $35$ GeV. The results are in an agreement with the measurement by the CMS experiment in $pp$ collisions at $\sqrt{s}=2.76$ TeV and $p_{\perp\min} = 35$ GeV within the theoretical and experimental uncertainties. The predictions of the NLL BFKL calculation of ratios of the MN cross sections at different collision energies and $p_{\perp\min}$ are also presented.
7.Jet quenching in mini-quark-gluon plasma: Medium modification factor $I_{pA}$ for photon-tagged jets
Authors:B. G. Zakharov
Abstract: We calculate the medium modification factor $I_{pA}$ for the photon-tagged jet fragmentation functions for scenario with the quark-gluon plasma formation in $pA$ and $pp$ collisions. We perform calculations of radiative and collisional parton energy loss in the quark-gluon plasma with running $\alpha_s$ which has a plateau around $Q\sim \kappa T$ with $\kappa$ fitted to the LHC data on the heavy ion $R_{AA}$. We find that the theoretical prediction for $I_{pA}$ in $5.02$ TeV $p$+Pb collisions are within errors consistent with the data from ALICE [1]. However, a definite conclusion about the presence or absence of jet quenching in $pA$ collisions cannot be drawn due to large experimental errors of the ALICE data [1]. Our calculations show that this requires a significantly more accurate measurement of $I_{pA}$.
8.$τ$ data-driven evaluation of Euclidean windows for the hadronic vacuum polarization
Authors:Pere Masjuan, Alejandro Miranda, Pablo Roig
Abstract: We compute for the first time the $\tau$ data-driven Euclidean windows for the hadronic vacuum polarization contribution to the muon $g-2$. We show that $\tau$-based results agree with the available lattice window evaluations and with the full result. On the intermediate window, where all lattice evaluations are rather precise and agree, $\tau$-based results are compatible with them. This is particularly interesting, given that the disagreement of the $e^+e^-$ data-driven result with the lattice values in this window is the main cause for their discrepancy, affecting the interpretation of the $a_\mu$ measurement in terms of possible new physics.
1.The QCD Axion: A Unique Player in the Axiverse with Mixings
Authors:Kai Murai, Fuminobu Takahashi, Wen Yin
Abstract: In an axiverse with numerous axions, the cosmological moduli problem poses a significant challenge because the abundance of axions can easily exceed that of dark matter. The well-established stochastic axion scenario offers a simple solution, relying on relatively low-scale inflation. However, axions are typically subject to mixing due to mass and kinetic terms, which can influence the solution using stochastic dynamics. Focusing on the fact that the QCD axion has a temperature-dependent mass, unlike other axions, we investigate the dynamics of the QCD axion and another axion with mixing. We find that the QCD axion abundance is significantly enhanced and becomes larger than that of the other axion for a certain range of parameters. This enhancement widens the parameter regions accounting for dark matter. In addition, we also find a parameter region in which both axions have enhanced abundances of the same order, which result in multi-component dark matter.
2.Fate of the topological susceptibility in two-color dense QCD
Authors:Mamiya Kawaguchi, Daiki Suenaga
Abstract: We explore the topological susceptibility at finite quark chemical potential and zero temperature in two-color QCD (QC$_2$D) with two flavors. Through the Ward-Takahashi identities of QC$_2$D, we find that the topological susceptibility in the vacuum solely depends on three observables: the pion decay constant, the pion mass, and the $\eta$ mass in the low-energy regime of QC$_2$D. Based on the identities, we numerically evaluate the topological susceptibility at finite quark chemical potential using the linear sigma model with the approximate Pauli-Gursey $SU(4)$ symmetry. Our findings indicate that, in the absence of $U(1)_A$ anomaly effects represented by the Kobayashi-Maskawa-'t Hooft-type determinant interaction, the topological susceptibility vanishes in both the hadronic and baryon superfluid phases. On the other hand, when the $U(1)_A$ anomaly effects are present, the constant and nonzero topological susceptibility is induced in the hadronic phase, reflecting the mass difference between the pion and $\eta$ meson. Meanwhile, in the superfluid phase it begins to decrease smoothly. The asymptotic behavior of the decrement is fitted by the continuous reduction of the chiral condensate in dense QC$_2$D, which is similar to the behavior observed in hot three-color QCD matter. In addition, effects from the finite diquark source on the topological susceptibility are discussed. We expect that the present study provides a clue to shed light on the role of the $U(1)_A$ anomaly in cold and dense QCD matter.
3.Constraints on the dark Z model from the Higgs boson phenomenology
Authors:Dong-Won Jung, Kang Young Lee, Chaehyun Yu
Abstract: We study constraints on the hidden sector model mediated by an additional SU(2) Higgs doublet from the phenomenology of Higgs bosons. The hidden sector is assumed to contain a hidden U(1) gauge symmetry and the hidden U(1) gauge boson gets the mass by the electroweak symmetry breaking to be a dark Z boson. The Higgs sector of the model is similar to that of the two Higgs doublet model of type I except for the absence of the CP-odd scalar boson. Using the programs of HiggsBounds and HiggsSignals, we incorporate current experimental limits from LEP, Tevatron and LHC to examine the Higgs sector in our model and derive constraints on model parameters. We also discuss the implications of the model on the dark matter phenomenology.
4.Forward-backward correlations with the $Σ$ quantity in the wounded constituent framework at LHC energies
Authors:Iwona Anna Sputowska
Abstract: $\Sigma$ is a new correlation measure, quite recently introduced to heavy-ion physics. This measure, defined in the independent source model as a strongly intensive quantity, is expected to be free of the effects of system volume and volume fluctuations. This paper discusses the forward-backward correlation quantified with the $\Sigma$ observable calculated in the framework of the wounded nucleon model (WNM) and wounded quark model (WQM). Findings show that the wounded constituent approach outperforms the commonly used heavy-ion Monte Carlo generators, such as HIJING, AMPT or EPOS, by accurately describing the experimental data on FB correlations with $\Sigma$ measured by ALICE in Xe--Xe reactions at $\sqrt{s_{\rm{NN}}}$=5.44 TeV and in Pb--Pb collisions at $\sqrt{s_{\rm{NN}}}$= 2.76 and 5.02 TeV. This paper demonstrates that $\Sigma$ can be a unique tool for determining the fragmentation function of a wounded constituent in a symmetric nucleus-nucleus collision. However, in the wounded constituent framework, it is no longer a strongly intensive quantity.
5.Unified triquark equations
Authors:A. N. Kvinikhidze, B. Blankleider
Abstract: We derive covariant equations describing the three-quark bound state in terms of quark and diquark degrees of freedom. The equations are exact in the approximation where three-body forces are neglected. A feature of these equations is that they unify two often-used but seemingly unrelated approaches that model baryons as quark-diquark systems; namely, (i) the approach using Poincar\'{e} covariant quark+diquark Faddeev equations driven by a one-quark-exchange kernel [pioneered by Cahill {\it et al.}, Austral.\ J.\ Phys.\ {\bf 42}, 129 (1989) and Reinhardt, Phys.\ Lett.\ B {\bf 244}, 316 (1990)], and (ii) the approach using the quasipotential quark-diquark bound-state equation where the kernel consists of the lowest-order contribution from an underlying quark-quark potential [pioneered by Ebert {\it et al.}, Z.\ Phys.\ C {\bf 76} 111 (1997)]. In particular, we show that each of these approaches corresponds to the unified equations with its kernel taken in different, non-overlapping, approximations.
6.The Global Fits of New Physics in $b \to s $ after $R_{K^{(*)}}$ 2022 Release
Authors:Qiaoyi Wen, Fanrong Xu
Abstract: The measurement of lepton universality parameters $R_{K^{(*)}}$ was updated by LHCb in December 2022, which indicated that the well-known anomalies in flavor-changing neutral current (FCNC) processes of B meson decays have faded away. However, does this mean that all new physics possibilities related to $b\to s\ell^+\ell^-$ have been excluded? We aim to answer this question in this work. The state-of-the-art effective Hamiltonian is adopted to describe $b \to s$ transition, while BSM (beyond the Standard Model) new physics effects are encoded in Wilson coefficients (WCs). Using around 200 observables in leptonic and semileptonic decays of B mesons and bottom baryons, measured by LHCb, CMS, ATLAS, Belle, and BaBar, we perform global fits of these Wilson coefficients in four different scenarios. In particular, lepton flavors in WCs are specified in some of the working scenarios. To see the change of new physics parameters, we use both the data before and after the 2022 release of $R_{K^{(*)}}$ in two separate sets of fits. We find that in all four scenarios, $\Delta C_9^\mu$ still has a deviation more than $4\sigma$ from the Standard Model. At the $1\sigma$ level, the lepton flavor in WCs is distinguishable for $\Delta C_{9, S, P}$ but indistinguishable for $\Delta C_{10}$. We demonstrate numerically that there is no chirality for muon type of scalar operator and it is kept at the $1\sigma$ level for their electron type dual ones, while chiral difference exists for $\mathcal{O}_{9,10}^\mu$ at least at the $2\sigma$ level.
7.Distinguishing the spins of $P_c(4440)$ and $P_c(4457)$ with femtoscopic correlation functions
Authors:Zhi-Wei Liu, Jun-Xu Lu, Ming-Zhu Liu, Li-Sheng Geng
Abstract: The spins of the pentaquark states $P_c(4440)$ and $P_c(4457)$ play a decisive role in unraveling their nature, but remain undetermined experimentally. Assuming that they are $\Sigma_c\bar{D}^{*}$ bound states, we demonstrate how one can determine their spins by measuring the $\Sigma_c^+\bar{D}^{(*)0}$ correlation functions. We show that one can use the $\Sigma_c^+\bar{D}^0$ correlation function to fix the size of the Gaussian source and then determine the strength of the $\Sigma_c^+\bar{D}^{*0}$ interaction of spin $1/2$ and $3/2$ and therefore the spins of the $P_c(4440)$ and $P_c(4457)$ states. The method proposed can be applied to decipher the nature of other hadronic molecules and thus deepen our understanding of the non-perturbative strong interaction.
8.$P_c$ states and their open-charm decays with the complex scaling method
Authors:Zi-Yang Lin, Jian-Bo Cheng, Bo-Lin Huang, Shi-Lin Zhu
Abstract: A partial width formula is proposed using the analytical extension of the wave function in momentum space. The distinction of the Riemann sheets is explained from the perspective of the Schrodinger equation. The analytical form in coordinate space and the partial width are derived subsequently. Then a coupled-channel analysis is performed to investigate the open-charm branching ratios of the $P_c$ states, involving the contact interactions and one-pion-exchange potential with the three-body effects. The low energy constants are fitted using the experimental masses and widths as input. The $P_c(4312)$ is found to decay mainly to $\Lambda_c\bar{D}^*$, while the branching ratios of the $P_c(4440)$ and $P_c(4457)$ in different channels are comparable. Under the reasonable assumption that the off-diagonal contact interactions are small, the $J^P$ quantum numbers of the $P_c(4440)$ and the $P_c(4457)$ prefer $\frac{1}{2}^-$ and $\frac{3}{2}^-$ respectively. Three additional $P_c$ states at 4380 MeV, 4504 MeV and 4516 MeV, together with their branching ratios, are predicted. A deduction of the revised one-pion-exchange potential involving the on-shell three-body intermediate states is performed.
9.Mechanical structures inside proton with configurational entropy language
Authors:Wei Kou, Xurong Chen
Abstract: The structure of the proton remains a significant challenge within the field of Quantum Chromodynamics, with the origin of its spin and mass still lacking a satisfactory explanation. In this study, we utilize the gravitational form factor of the proton as the foundation for constructing the configurational entropy of the proton energy system. Employing this approach, we are able to determine key mechanical quantities such as the proton's mass radius and pressure distribution. Our analysis yields the root-mean-square mass radius of $\sqrt{\langle r_M^2\rangle}=0.720$ fm and scalar radius of $\sqrt{\langle r_S^2\rangle}=1.024$ fm for proton, which are found to be in excellent agreement with recent measurements from the Hall-C collaboration group at Jefferson Lab. Additionally, we examine the radial distribution of pressure and shear force within the proton.
10.The potential and string breaking of doubly heavy baryon at finite temperature and chemical potential
Authors:Bo Yu, Xi Guo, Xiao-Hua Li, Xun Chen
Abstract: Using gauge/gravity duality, we study the string breaking and melting of doubly heavy baryon at a finite chemical potential and temperature. The decay mode $\rm{Q Q q \rightarrow Q q q+Q \bar{q}}$ is investigated in this paper. With the increase of temperature and chemical potential, string breaking takes place at a smaller potential energy. It is also found that the QQq melts at small separate distance with the increase of temperature and chemical potential. Then, we compare the screening distance of QQq with $\rm{Q \bar{Q}}$ under the same conditions. Finally, we draw the melting diagram of QQq and $\rm{Q \bar{Q}}$ in the $T-\mu$ plane.
11.Interpreting dark matter solution for $B-L$ gauge symmetry
Authors:Phung Van Dong
Abstract: It is shown that the solution for $B-L$ gauge symmetry with $B-L=-4,-4,+5$ assigned for three right-handed neutrinos respectively, reveals a novel scotogenic mechanism with implied matter parity for neutrino mass generation and dark matter stability. Additionally, the world with two-component dark matter is hinted.
12.Unitarity, real-intermediate states, and fixed-order approach to resonant dark matter annihilation
Authors:Peter Maták
Abstract: We study the role of perturbative unitarity in the resonant annihilation of two dark matter particles into the standard model bath. Systematically including all kinematically allowed holomorphic cuts of the corresponding forward-scattering diagram, cancellation of the singularities occurs, resulting in a fixed-order correction to the narrow-width approximation for the annihilation cross section. Unlike the standard approach based on including the finite width of the mediator, no double-counting of intermediate states occurs.
1.Phenomenological implications of nonlocal quantum electrodynamics
Authors:Antonio Capolupo, Aniello Quaranta, Raoul Serao
Abstract: We analyze several phenomenological implications of a nonlocal generalization of quantum electrodynamics (QED). We compute the nonlocal corrections to the photon propagator up to one loop, and we show that nonlocality leads to a change of the Coulomb potential. We then investigate the ensuing modifications to the Lamb shift and to the electrostatic forces and comparing our results with the data from the muonic hydrogen anomaly, we set lower bounds on the nonlocality scales. We also discuss the running of the electromagnetic coupling for the nonlocal theory. The results obtained indicate that future experimental analyses on atomic phenomena, such as the Lamb shift, could allow to verify the presence of non-local effects on microscopic scales and impose effective limits on the non-locality scale.
2.Thermal Leptogenesis in the Minimal Gauged $U(1)_{L_μ-L_τ}$ Model
Authors:Alessandro Granelli, Koichi Hamaguchi, Natsumi Nagata, Maura E. Ramirez-Quezada, Juntaro Wada
Abstract: We discuss the thermal leptogenesis mechanism within the minimal gauged U(1)$_{L_\mu-L_\tau}$ model to explain the observed baryon asymmetry of the Universe (BAU). In such framework, the phases of the Pontecorvo-Maki-Nakagawa-Sakata neutrino mixing matrix and the sum of the Standard Model neutrino masses are predictable because of a restricted neutrino mass matrix structure. Additionally, in the context of thermal leptogenesis, the BAU can be computed in terms of the three remaining free variables that parameterise the right-handed neutrino masses and their Yukawa couplings to the Higgs and lepton doublets. We identify the ranges of such parameters for which the correct BAU can be reproduced. We adopt the formalism of the density matrix equations to fully account for flavour effects and consider the decays of all the three right-handed neutrinos. Our analysis reveals that thermal leptogenesis is feasible within a wide parameter space, specifically for Yukawa couplings ranging from approximate unity to $\mathcal{O}(0.03-0.05)$ and mass of the lightest right-handed neutrino $M_1\gtrsim 10^{11-12}\,\text{GeV}$, setting a leptogenesis scale in the considered model which is higher than that of the non-thermal scenario.
3.Tamed loops: a way to obtain finite loop results without UV divergences
Authors:Lian-Bao Jia
Abstract: For loops with UV divergences, finite physical results obtained via $\infty - \infty$ mean the physical transition amplitudes of loops are not well-defined. In this paper, a presumption that the physical contributions of loops are finite with UV regions being insignificant is proposed, and a new method of UV-free scheme is introduced to derive finite physical results. In this scheme, finite loop results can be obtained without UV divergences, and the hierarchy problem of Higgs mass can be solved without fine-tuning.
4.First Extraction of Kaon Partonic Distribution Functions from Drell-Yan and $J/ψ$ Production Data
Authors:Claude Bourrely, Franco Buccella, Wen-Chen Chang, Jen-Chieh Peng
Abstract: We present an analysis to extract kaon parton distribution functions (PDFs) for the first time using meson-induced Drell-Yan and quarkonium production data. Starting from the statistical model first developed for determining the partonic structure of spin-1/2 nucleon and later applied to the spin-0 pion, we have extended this approach to perform a global fit to existing kaon-induced Drell-Yan and $J/\psi$ production data. These data are well described by the statistical model, allowing a first extraction of the kaon PDFs. We find that both the Drell-Yan and the $J/\psi$ data favor a harder valence distribution for strange quark than for up quark in kaon. The kaon gluon distribution is further constrained by the $J/\psi$ production data. In particular, the momentum fraction carried by gluons is found to be similar for pion and kaon.
5.Vacuum Stability as a Guide for Model Bulding
Authors:Gudrun Hiller, Tim Höhne, Daniel F. Litim, Tom Steudtner
Abstract: We explain why vector-like fermions are natural candidates to lift the Standard Model vacuum instability. Results are further discussed from the viewpoint of criticality. Several models allow for vector-like quarks and leptons in the TeV-range which can be searched for at the LHC.
6.Ultraviolet Sensitivity of Peccei--Quinn Inflation
Authors:Davide Dal Cin, Takeshi Kobayashi
Abstract: The radial direction of the Peccei--Quinn field can drive cosmic inflation, given a non-minimal coupling to gravity. This scenario has been considered to simultaneously explain inflation, the strong $CP$ problem, and dark matter. We argue that Peccei--Quinn inflation is extremely sensitive to higher-dimensional operators. Further combining with the discussion on the axion quality required for solving the strong $CP$ problem, we examine the validity of this scenario. We also show that after Peccei--Quinn inflation, resonant amplifications of the field fluctuation is inevitably triggered.
1.Fermionic Electroweak NNLO Corrections to \boldmath $e^+ e^- \to ZH$ with Polarized Beams and Different Renormalization Schemes
Authors:Ayres Freitas, Qian Song, Keping Xie
Abstract: Recently, the next-to-next-to-leading order (NNLO) electroweak corrections with fermion loops to the Higgsstrahling process were computed. Here we present numerical results for polarized electron/positron beams, as well as for two input parameter schemes known as the $\alpha(0)$ and $G_\mu$ schemes. The size of the NNLO corrections strongly depends on the beam polarization, leading to an increase of the $ZH$ cross-section by 0.76\% for $e^+_{\rm L} e^-_{\rm R}$ beams, and a decrease of 0.04\% for $e^+_{\rm R} e^-_{\rm L}$ beams. Furthermore, inclusion of the NNLO corrections is found to significantly reduce the discrepancy between the results in the $\alpha(0)$ and $G_\mu$ schemes. Using the remaining difference, together with other methods, the theory uncertainty from missing bosonic electroweak corrections is estimated to be less than 0.3\%.
2.Study lepton flavor violation $B_d\rightarrow{{l_i}^{\pm}{l_j}^{\mp}}$ within the Mass Insertion Approximation
Authors:Yi-Tong Wang, Shu-Min Zhao, Xin-Xin Long, Xi Wang, Tong-Tong Wang, Hai-Bin Zhang, Tai-Fu Feng
Abstract: We study lepton flavor violating (LFV) decays $B_d\rightarrow{{l_i}^{\pm}{l_j}^{\mp}}$($B_d\rightarrow e{\mu}$, $B_d\rightarrow e{\tau}$ and $B_d\rightarrow {\mu}{\tau}$) in the $U(1)_X$SSM, which is the $U(1)$ extension of the minimal supersymmetric standard model. The local gauge group of $U(1)_X$SSM model is $SU(3)_C\times SU(2)_L \times U(1)_Y \times U(1)_X$. These processes are virtually forbidden in the standard model(SM), but they can induce decay that violates lepton flavor in the new physics model. We use the Mass Insertion Approximation(MIA) to find sensitive parameters that directly influence the result of the branching ratio of LFV decay $B_d\rightarrow{{l_i}^{\pm}{l_j}^{\mp}}$. Combined with the latest experimental results, we analyze the relationship between different sensitive parameters and the branching ratios of the three processes. According to the numerical analysis, we can conclude that the main sensitive parameters and LFV sources are the non-diagonal elements corresponding to the initial and last lepton generations.
3.Prediction of charmed-bottom pentaquarks in quark model
Authors:Ye Yan, Yuheng Wu, Hongxia Huang, Jialun Ping, Xinmei Zhu
Abstract: Inspired by the fully heavy tetraquark states reported by the LHCb, ATLAS and CMS Collaborations, we perform a systemical investigation of the low-lying fully heavy pentaquark systems composed of charm and bottom quarks (anti-quark) in the chiral quark model. With the help of the channel-coupling, we obtain several fully heavy pentaquark candidates, which are $cccc\bar{b}$ and $bbbb\bar{c}$ systems with $J^P = 1/2^-$ and $3/2^-$, $cccb\bar{c}$, $bbbc\bar{b}$, $cccb\bar{b}$ and $bbbc\bar{c}$ systems with $J^P = 5/2^-$. The binding energies of these states are all below 10 MeV and the root mean square (RMS) are around 1.8 fm, which indicates that these states are likely to be molecular states. These predicted exotic states may provide new ideas for experimental searches and we expect more experimental and theoretical researches to study and understand the fully heavy states in future.
4.Chemical freeze-out parameters via functional renormalization group approach
Authors:Jun-xiang Shao, Wei-jie Fu, Yu-xin Liu
Abstract: We study the freeze-out parameters in a QCD-assisted effective theory that accurately captures the quantum and in-medium effects of QCD at low energies. Functional renormalization group approach is implemented in our work to incorporate the non-perturbative quantum, thermal and density fluctuations. By analyzing the calculated baryon number susceptibility ratios $\chi_{2}^{B}/\chi_{1}^{B}$ and $\chi_{3}^{B}/\chi_{2}^{B}$, we determine the chemical freeze-out temperatures and baryon chemical potentials in cases of hard thermal or dense loop improved $\mu$-dependent glue potential and $\mu$-independent glue potential. We calculate the ${\chi_{4}^{B}}/{\chi_{2}^{B}}\, (\kappa \sigma^{2})$ and ${\chi_{6}^{B}}/{\chi_{2}^{B}}$ along the freeze-out line for both cases. It's found that $\kappa \sigma^{2}$ exhibits a nonmonotonic behavior in low collision energy region and approach to one for lower collision energy. ${\chi_{6}^{B}}/{\chi_{2}^{B}}$ shows a similar complicated behavior in our calculation.
5.Effective Field Theories of Axion, ALP and Dark Photon
Authors:Huayang Song, Hao Sun, Jiang-Hao Yu
Abstract: With the help of Young tensor technique, we enumerate the complete and independent set of effective operators up to $dim$-8 for the extension of the standard model with a Goldsonte boson by further imposing the Adler's zero condition in the soft momentum limit. Such basis can be reduced to describe the axion or majoron effective Lagrangian if further (symmetry) constraints are imposed. Then reformulating dark photon as combination of Goldstone boson and transverse gauge boson, the effective operators of the Goldstone boson can be extended to effective chiral Lagrangian description of the dark photon. For the first time we obtain 0 (0), 6 (44), 1 (1), 44 (356), 32 (520) operators in Goldstone effective field theory, and 9 (49), 0 (0), 108 (676), 10 (426), 1904 (40783) operators in dark photon effective field theory at the dimension 4, 5, 6, 7, 8 for one (three) generation of fermions.
6.How to Understand Limitations of Generative Networks
Authors:Ranit Das, Luigi Favaro, Theo Heimel, Claudius Krause, Tilman Plehn, David Shih
Abstract: Well-trained classifiers and their complete weight distributions provide us with a well-motivated and practicable method to test generative networks in particle physics. We illustrate their benefits for distribution-shifted jets, calorimeter showers, and reconstruction-level events. In all cases, the classifier weights make for a powerful test of the generative network, identify potential problems in the density estimation, relate them to the underlying physics, and tie in with a comprehensive precision and uncertainty treatment for generative networks.
7.Looking forward to photon-coupled long-lived particles III: inelastic DM with EM form factors
Authors:Krzysztof Jodłowski
Abstract: Inelastic Dark Matter (iDM) is an interesting thermal DM scenario that can pose challenges for conventional detection methods. However, recent studies demonstrated that iDM coupled to a photon by electric or magnetic dipole moments can be effectively constrained by intensity frontier experiments using the displaced single-photon decay signature. In this work, we show that by utilizing additional signatures for such models, the sensitivity reach can be increased towards the short-lived regime, $\gamma c\tau \sim O(1)\,$m, which can occur in the region of the parameter space relevant to successful thermal freeze-out. These processes are secondary iDM production taking place by upscattering in front of the decay vessel and electron scattering. Additionally, we consider dimension-6 scenarios of photon-coupled iDM - the anapole moment and the charge radius operator - where the leading decay of the heavier iDM state is $\chi_1 \to \chi_0 e^+ e^-$, resulting in a naturally long-lived $\chi_1$. We find that the decays of $\chi_1$ at FASER2, MATHUSLA, and SHiP will constrain these models more effectively than the scattering signature considered for the elastic coupling case, while secondary production yields similar constraints as the scattering.
8.CP and T violation effects in presence of an $\mbox{eV}$ scale sterile neutrino at long baseline neutrino experiments
Authors:Sabila Parveen, Kiran Sharma, Sudhanwa Patra, Poonam Mehta
Abstract: An important goal of current and future long baseline neutrino oscillation experiments pertains to determination of the Dirac-type leptonic $CP$ phase, $\delta_{13}$. We consider the new physics scenario of an eV scale sterile neutrino along with three active neutrinos and demonstrate the impact on the $CP$ and $T$ violation measurements in neutrino oscillations. We address the question of disentangling the intrinsic effects from extrinsic effects in the standard three neutrino paradigm as well as the scenario with added light sterile neutrino. We define a metric to isolate the two kinds of effects and our approach is general in the sense that it is independent of the choice of $\delta_{13}$. We study the role of different appearance and disappearance channels which can contribute to CP and T violation measurements. We perform the analysis for different long baseline experiments which have different detection capabilities such as Water Cherenkov (WC) and Liquid Argon Time Projection Chamber (LArTPC).
9.Photon to axion conversion during Big Bang Nucleosynthesis
Authors:Antonio J. Cuesta, José I. Illana, Manuel Masip
Abstract: We investigate how the resonant conversion at a temperature $\bar{T}=25$-$65$ keV of a fraction of the CMB photons into an axion-like majoron affects BBN. The scenario, that assumes the presence of a primordial magnetic field and the subsequent decay of the majorons into neutrinos at $T\approx 1$ eV, has been proposed to solve the $H_0$ tension. We find two main effects. First, since we lose photons to majorons at $\bar{T}$, the baryon to photon ratio is smaller at the beginning of BBN $(T>\bar{T})$ than during decoupling and structure formation ($T\ll \bar{T}$). This relaxes the $2\sigma$ mismatch between the observed deuterium abundance and the one predicted by the standard $\Lambda$CDM model. Second, since the conversion implies a sudden drop in the temperature of the CMB during the final phase of BBN, it interrupts the synthesis of lithium and beryllium and reduces their final abundance, possibly alleviating the lithium problem.
10.Perturbative aspects of mass dimension one fermions non-minimally coupled to electromagnetic field
Authors:Willian Carvalho, M. Dias, A. C. Lehum, J. M. Hoff da Silva
Abstract: This paper addresses perturbative aspects of the renormalization of a fermion with mass dimension one non-minimally coupled to the electromagnetic field. Specifically, we calculate the one-loop corrections to the propagators and vertex functions of the model and determine the one-loop beta function of the non-minimal electromagnetic coupling. Additionally, we perform calculations of the two-loop corrections to the gauge field propagator, demonstrating that it remains massless and transverse up to this order. We also find that the non-minimal electromagnetic coupling can exhibit asymptotic freedom if a certain condition is satisfied. As a potential dark matter candidate, these findings suggest that the field may decouple at high energies. This aspect holds significance for calculating the relic abundance and freeze-out temperature of the field, particularly in relation to processes involving the ordinary particles of the Standard Model.
11.Dirac-Majorana neutrino type conversion induced by an oscillating scalar dark matter
Authors:YeolLin ChoeJo, Yechan Kim, Hye-Sung Lee
Abstract: Some properties of a neutrino may differ significantly depending on whether it is Dirac or Majorana type. The type is determined by the relative size of Dirac and Majorana masses, which may vary if they arise from an oscillating scalar dark matter. We show that the change can be significant enough to convert the neutrino type between Dirac and Majorana while satisfying constraints on the dark matter. It predicts periodic modulations in the event rates in various neutrino phenomena. As the energy density and, thus, the oscillation amplitude of the dark matter evolves in the cosmic time scale, the relative size of Dirac and Majorana masses changes accordingly. It provides an interesting link between the present-time neutrino physics to the early universe cosmology including the leptogenesis.
12.Sensitivity prospects for lepton-trijet signals in the $ν$SMEFT at the LHeC
Authors:Gabriel Zapata, Tomás Urruzola, Oscar A. Sampayo, Lucía Duarte
Abstract: The observation of neutrino oscillations and masses motivates the extension of the standard model with right handed neutrinos, leading to heavy neutrino states possibly in the electroweak scale, which could be impacted by new high-scale weakly coupled physics. A systematic tool for studying these interactions is the neutrino-extended standard model effective field theory $\nu$SMEFT. In this work we study the prospects of the future LHeC electron-proton collider to discover or constrain the $\nu$SMEFT interactions, performing the first dedicated and realistic analysis of the well known lepton-trijet signals, both for the lepton flavor violating $p ~ e^{-} \rightarrow \mu^{-} + 3 \mathrm{j}$ (LFV) and the lepton number violating $p ~ e^{-} \rightarrow \mu^{+} + 3 \mathrm{j}$ (LNV) channels, for HNLs masses in the electroweak scale range: $100 ~\rm GeV \leq m_N \leq 500 ~\rm GeV$. The obtained sensitivity prospects show that the LHeC with $100 ~\rm fb^{-1}$ luminosity could be able to probe the scenario of a heavy $N$ and constrain the effective couplings to a region of the parameter space as tight as the bounds that are currently considered for the $\mathcal{O}(10)$GeV scale masses, with effective couplings of $\mathcal{O}(10^{-1})$ for NP scale $\Lambda=1 \rm TeV$.
13.Cabibbo suppressed hyperon production off nuclei induced by antineutrinos
Authors:M. Benitez Galan, L. Alvarez-Ruso, M. Rafi Alam, I. Ruiz Simo, M. J. Vicente Vacas
Abstract: In this work we study the production of $\Sigma$ and $\Lambda$ hyperons in strangeness changing $\Delta S = -1$ charged current interactions of muon antineutrinos on nuclear targets. At the nucleon level, besides quasielastic scattering we consider the inelastic mechanism in which a pion is produced alongside the hyperon. Its relevance for antineutrinos with energies below 2 GeV is conveyed in integrated and differential cross sections. We observe that the distributions on the angle between the hyperon and the final lepton are clearly different for quasielastic and inelastic processes. Hyperon final state interactions, modeled with an intranuclear cascade, lead to a significant transfer from primary produced $\Sigma$'s into final $\Lambda$'s. They also cause considerable energy loss, which is apparent in hyperon energy distributions. We have investigated $\Lambda$ production off ${}^{40}$Ar in the conditions of the recently reported MicroBooNE measurement. We find that the $\Lambda \pi$ contribution, dominated by $\Sigma^*(1385)$ excitation, accounts for about one third of the cross section.
14.Quantum Spread Complexity in Neutrino Oscillations
Authors:Khushboo Dixit, S. Shajidul Haque, Soebur Razzaque
Abstract: Quantum information theory has recently emerged as a flourishing area of research and quantum complexity, one of its powerful measures, is being applied for investigating complex systems in many areas of physics. Its application to practical physical situations, however, is still few and far between. Neutrino flavor oscillation is a widely studied physical phenomena with far reaching consequences in understanding the standard model of particle physics and to search for physics beyond it. Oscillation arises because of mixing between the flavor and mass eigenstates, and their evolution over time. It is an inherent quantum system for which flavor transitions are traditionally studied with probabilistic measures. We have applied quantum complexity formalism as an alternate measure to study neutrino oscillations. In particular, quantum spread complexity revealed additional information on the violation of charge-parity symmetry in the neutrino sector. Our results indicate that complexity favors the maximum violation of charge-parity, hinted recently by experimental data.
15.Two-Loop QCD Corrections for Three-Photon Production at Hadron Colliders
Authors:Samuel Abreu, Giuseppe De Laurentis, Harald Ita, Maximillian Klinkert, Ben Page, Vasily Sotnikov
Abstract: We complete the computation of the two-loop helicity amplitudes for the production of three photons at hadron colliders, including all contributions beyond the leading-color approximation. We reconstruct the analytic form of the amplitudes from numerical finite-field samples obtained with the numerical unitarity method. This method requires as input surface terms for all relevant five-point non-planar integral topologies, which we obtain by solving the associated syzygy problem in embedding space. The numerical samples are used to constrain compact spinor-helicity ans\"atze, which are optimized by taking advantage of the known one-loop analytic structure. We make our analytic results available in a public C++ library, which is suitable for immediate phenomenological applications. We estimate that the inclusion of the subleading-color contributions will decrease the size of the two-loop corrections by about 30% to 50% compared to the results in the leading-color approximation.
16.Fitting a Deep Generative Hadronization Model
Authors:Jay Chan, Xiangyang Ju, Adam Kania, Benjamin Nachman, Vishnu Sangli, Andrzej Siodmok
Abstract: Hadronization is a critical step in the simulation of high-energy particle and nuclear physics experiments. As there is no first principles understanding of this process, physically-inspired hadronization models have a large number of parameters that are fit to data. Deep generative models are a natural replacement for classical techniques, since they are more flexible and may be able to improve the overall precision. Proof of principle studies have shown how to use neural networks to emulate specific hadronization when trained using the inputs and outputs of classical methods. However, these approaches will not work with data, where we do not have a matching between observed hadrons and partons. In this paper, we develop a protocol for fitting a deep generative hadronization model in a realistic setting, where we only have access to a set of hadrons in data. Our approach uses a variation of a Generative Adversarial Network with a permutation invariant discriminator. We find that this setup is able to match the hadronization model in Herwig with multiple sets of parameters. This work represents a significant step forward in a longer term program to develop, train, and integrate machine learning-based hadronization models into parton shower Monte Carlo programs.
17.Interaction field strength between a scalar particle and two massless vector bosons in presence of an external magnetic field
Authors:Jorge Jaber-Urquiza, Angel Sanchez
Abstract: In this work we study the interaction strength among a neutral scalar boson and two massless vector bosons in presence of an external magnetic field. Based on global symmetries, we build the general tensor structure amplitude $\mathcal{M}^{\mu\nu}$, for the process $V^\mu+V^\nu\longrightarrow\phi$, in terms of the vector bosons polarization states. Then, we present a novel methodology to compute the one-loop amplitude contributions for an homogeneous magnetic field with arbitrary strength. With the obtained results, expressed in terms of integrals over Schwinger parameters, we explore its behavior in two regions, widely used in the literature, the strong and weak field strength regions. The methodology presented in this work can be employed to compute an arbitrary process in presence of an external magnetic field where the initial and final states are neutral.
1.$Z_{cs}$, $Z_c$ and $Z_b$ states under the complex scaling method
Authors:Jian-Bo Cheng, Bo-Lin Huang, Zi-Yang Lin, Shi-Lin Zhu
Abstract: We investigate the $Z_b$, $Z_c$ and $Z_{cs}$ states within the chiral effective field theory framework and the $S$-wave single channel molecule picture. With the complex scaling method, we accurately solve the Schr\"odinger equation in momentum space. Our analysis reveals that the $Z_b(10610)$, $Z_b(10650)$, $Z_c(3900)$ and $Z_c(4020)$ states are the resonances composed of the $S-$wave $(B\bar{B}^{*}+B^{*}\bar{B})/\sqrt{2}$, $B^{*}\bar{B}^*$, $(D\bar{D}^{*}+D^{*}\bar{D})/\sqrt{2}$ and $D^{*}\bar{D}^*$, respectively. Furthermore, although the $Z_{cs}(3985)$ and $Z_{cs}(4000)$ states exhibit a significant difference in width, these two resonances may originate from the same channel, the $S-$wave $(D_{s}\bar{D}^{*}+D_{s}^{*}\bar{D})/\sqrt{2}$. Additionally, we find two resonances in the $S-$wave $D_s^*\bar{D}^*$ channel, corresponding to the $Z_{cs}(4123)$ and $Z_{cs}(4220)$ states that await experimental confirmation.
2.The magnetic properties of a deuteron $r_m$ from the AdS/QCD hard-wall model
Authors:Minaya Allahverdiyeva, Narmin Huseynova, Shahin Mamedov, Jannat Samadov
Abstract: The deuteron is a spin1 particle and due to current conservation and the P and C invariance of the EM interaction, it has three EM form factors in the one photon exchange (OPE) approximation, which include the charge GC(Q2), quadrupole GQ(Q2) and magnetic GM(Q2) form factors and was calculated in [1, 2, 3] at a zero temperature within soft-wall and hard-wall models AdS/QCD. In this work, we numerically calculated the deuteron magnetic radius RM in the framework of the hard-wall model of AdS/QCD and compare our results with the experimental data and soft-wall model results [2]
3.Quantum version of transport coefficients in Nambu--Jona-Lasinio model at finite temperature and strong magnetic field
Authors:Aritra Bandyopadhyay, Snigdha Ghosh, Ricardo L. S. Farias, Sabyasachi Ghosh
Abstract: We have estimated parallel and perpendicular components of electrical conductivity and shear viscosity of quark matter at finite magnetic field and temperature by using their one-loop Kubo expressions in the framework of Nambu--Jona-Lasinio (NJL) model. At finite magnetic field, a non-trivial medium dependence of those quantities can be found. Previously these NJL-profiles have been addressed in relaxation time approximation, where cyclotron motion of quarks with medium dependent mass plays the key role. With respect to the earlier estimations, the present work provides further enriched profiles via Kubo framework, where field theoretical descriptions of quark transport with medium dependent mass and (Landau) quantized energy have been identified as the key ingredients. Hence the present study can be considered as the complete quantum field theoretical description of the transport coefficients in the framework of NJL model at finite temperature and magnetic field.
4.Diffractive Vector Meson production using Sar$t$re with Machine Learning
Authors:Jaswant Singh, Tobias Toll
Abstract: The event generator Sar$t$re has been used extensively for simulations of electron-ion collisions in preparation for the Electron-Ion Collider (EIC). Sar$t$re simulates exclusive diffraction in $e$A collisions, in principle for any nuclear species and exclusive final state, usually a vector meson. The coherent and incoherent cross sections for each process are calculated in the colour dipole model for small $x$ from the first and second moments of the respective amplitude, averaged over initial state spatial configurations. Taking these averages is a very CPU demanding task. In order to function as an efficient event generator, these amplitude moments are saved into lookup tables which are used as input for the event generation, making the latter a very fast process. However, there are many recent and ongoing developments of the dipole models underlying the calculations, both in terms of fits of the model parameters to new data as well as new parametrisations of the dipole or proton geometries. Therefore, it is desirable to have a more flexible method for producing the lookup tables. Here, we propose a method using neural networks which can reduce the table production time by 90\% while retaining the same precision in the resulting cross sections.
5.Identifying physics beyond SMEFT in the angular distribution of $Λ_b\rightarrow Λ_c(\rightarrowΛπ)τ\barν_τ$ decay
Authors:Siddhartha Karmakar, Susobhan Chattopadhyay, Amol Dighe
Abstract: Indirect searches of physics beyond the Standard Model (BSM) may be performed using the tool of effective field theory (EFT). In the Standard Model Effective Field Theory (SMEFT), the $SU(2)_L\times U(1)_Y$ symmetry of the Standard Model is linearly realized. However, it is possible that more general EFTs such as the Higgs Effective Field Theory (HEFT) are needed to describe the data. We explore the effects of scalar and vector new-physics operators that contribute to the charged-current processes $b\rightarrow c \tau\nu_\tau$. The angular distribution of $\Lambda_b\rightarrow \Lambda_c(\rightarrow\Lambda\pi)\tau\bar\nu_\tau$ decay is sensitive to the 6-dimensional effective operator $O_V^{LR}\equiv(\bar{\tau}\gamma^\mu P_L\nu_\tau)(\bar{c}\gamma_\mu P_R b)$, which is present in HEFT but suppressed in SMEFT. We identify the angular observables that can have significant contribution from $O_V^{LR}$, and hence would be useful for probing not only BSM physics but also physics beyond SMEFT.
6.On practical naturalness and its implications for weak scale supersymmetry
Authors:Howard Baer, Vernon Barger, Dakotah Martinez, Shadman Salam
Abstract: We revisit the various measures of naturalness for models of weak scale supersymmetry including 1. electroweak (EW) naturalness, 2. naturalness via sensitivity to high scale parameters (EENZ/BG), 3. sensitivity of Higgs soft term due to high scale (HS) radiative corrections and 4. stringy naturalness (SN) from the landscape. The EW measure is most conservative and seems unavoidable; it is also model independent in that its value is fixed only by the weak scale spectra which ensues, no matter which model is used to generate it. The EENZ/BG measure is ambiguous depending on which ``parameters of ignorance'' one includes in the low energy effective field theory (LE-EFT). For models with calculable soft breaking terms, then the EENZ/BG measure reduces to the tree-level EW measure. The HS measure began life as a figurative expression and probably shouldn't be taken more seriously than that. SN is closely related to EW naturalness via the atomic principle, although it is also sensitive to the distribution of soft terms on the landscape. If the landscape favors large soft terms, as in a power law distribution, then it favors m(h) ~ 125 GeV along with sparticles beyond present LHC reach. In this context, SN appears as a probability measure where more natural models are expected to be more prevalent on the landscape than finetuned models. We evaluate by how much the different measures vary against one another with an eye to determining by how much they may overestimate finetuning; we find overestimates can range up to a factor of over 1000. In contrast to much of the literature, we expect the string landscape to favor EW natural SUSY models over finetuned models so that the landscape is not an alternative to naturalness.
7.Dark Higgs Bosons at Colliders
Authors:Torben Ferber, Alexander Grohsjean, Felix Kahlhoefer
Abstract: The Large Hadron Collider (LHC) has confirmed the Higgs mechanism to be responsible for generating mass in the Standard Model (SM), making it attractive to also consider spontaneous symmetry breaking as the origin of mass for new particles in a dark sector extension of the SM. Such a dark Higgs mechanism may in particular give mass to a dark matter candidate and to the gauge boson mediating its interactions (called dark photon). In this review we summarise the phenomenology of the resulting dark Higgs boson and discuss the corresponding search strategies with a focus on collider experiments. We consider both the case that the dark Higgs boson is heavier than the SM Higgs boson, in which case leading constraints come from direct searches for new Higgs bosons as well missing-energy searches at the LHC, and the case that the dark Higgs boson is (potentially much) lighter than the SM Higgs boson, such that the leading sensitivity comes from electron-positron colliders and fixed-target experiments. Of particular experimental interest for both cases is the associated production of a dark Higgs boson with a dark photon, which subsequently decays into SM fermions, dark matter particles or long-lived dark sector states. We also discuss the important role of exotic decays of the SM-like Higgs boson and complementary constraints arising from early-universe cosmology, astrophysics and direct searches for dark matter in laboratory experiments.
8.Thermodynamics and phase diagrams of the Polyakov quark-meson model with on-shell versus curvature mass parameter fixing
Authors:Suraj Kumar Rai, Vivek Kumar Tiwari
Abstract: The Quantum Chromodynamics (QCD) phase structure has been studied using the Polyakov-loop augmented quark-meson model (PQM) in the extended mean field approximation (e-MFA) where the quark one-loop vacuum term is included.~When the divergent vacuum term is regularized in the minimal subtraction scheme and the curvature meson masses are used to fix the parameters,~the Polyakov quark-meson model with the vacuum term (PQMVT) becomes inconsistent as the curvature masses are determined by calculating the self energies at zero momentum.~The above inconsistency is remedied by the on-shell parameter fixing when the pion decay constant and the pole masses of the mesons are put into the relation of the couplings and running mass parameter by using the on-shell and the minimal subtraction renormalization scheme.~Combining the modified chiral effective potential of the on-shell renormalized quark-meson model (RQM) with the Polyakov-loop potential that mimics the physics of the confinement-deconfinement transition,~we get the renormalized Polyakov quark-meson (RPQM) model.~The phase diagrams and the thermodynamics details for the PQM, PQMVT and RPQM model, have been computed and compared for different forms of the Polyakov-loop potentials with and without the quark back-reaction.~The results have also been compared with the available lattice QCD data.~The so called quarkyonic phase region in the phase diagram, where the chiral symmetry is restored but the quarks and anti-quarks are still confined,~gets reduced by the quark back-reaction in the unquenched Polyakov-loop potential.~It altogether disappears for the chemical potential dependent parameter $T_{0} \equiv T_{0} (\mu)$ in the Log or the PolyLog-glue form of the Polyakov-loop potential in the RPQM model.
9.Higgs Inflation via the Metastable Standard Model Potential, Generalised Renormalisation Frame Prescriptions and Predictions for Primordial Gravitational Waves
Authors:J. McDonald
Abstract: Higgs Inflation via the unmodified metastable Standard Model Higgs Potential is possible if the effective Planck mass in the Jordan frame increases after inflation ends. Here we consider the predictions of this model independently of the dynamics responsible for the Planck mass transition. The classical predictions are the same as for conventional Higgs Inflation. The quantum corrections are dependent upon the conformal frame in which the effective potential is calculated. We generalise beyond the usual Prescription I and II renormalisation frame choices to include intermediate frames characterised by a parameter $\alpha$. We find that the model predicts a well-defined correlation between the values of the scalar spectral index $n_{s}$ and tensor-to-scalar ratio $r$. For values of $n_{s}$ varying between the 2-$\sigma$ Planck observational limits, we find that $r$ varies between 0.002 and 0.005 as $n_{s}$ increases, compared to the classical prediction of 0.003. Therefore significantly larger or smaller values of $r$ are possible, which are correlated with larger or smaller values of $n_{s}$. This can be tested via the detection of primordial gravitational waves by the next generation of CMB polarisation experiments.
10.Capability of the proposed long-baseline experiments to probe large extra dimension
Authors:Samiran Roy
Abstract: Future long-baseline experiments will play an important role in exploring physics beyond the standard model. One such new physics concept is the large extra dimension (LED), which provides an elegant solution to the hierarchy problem. This model also explains the small neutrino mass in a natural way. The presence of LED modifies the standard neutrino oscillation probabilities. Hence, the long-baseline experiments are sensitive to the LED parameters. We explore the potential of the three future long-baseline neutrino experiments, namely T2HK, ESSnuSB, and DUNE, to probe the LED parameter space. We also compare the capability of the charged and neutral current measurements at DUNE to constrain the LED model. We find that T2HK will provide more stringent bounds on the largest compactification radius ($R_{\rm{ED}}$) compared to the DUNE and ESSnuSB experiments. At $90\%$ C.L., T2HK can exclude $R_{\rm{ED}}\sim 0.45~(0.425)$ $\mu$m for the normal (inverted) mass hierarchy scenario.
11.The complex heavy-quark potential with the Gribov-Zwanziger action
Authors:Manas Debnath, Ritesh Ghosh, Najmul Haque
Abstract: Gribov-Zwanziger prescription in Yang-Mills theory improves the infrared dynamics. In this work, we study the static potential of a heavy quark-antiquark pair with the HTL resummed perturbation method within the Gribov-Zwanziger approach at finite temperature. The real and imaginary parts of the heavy quark complex potential are obtained from the one-loop effective static gluon propagator. The one-loop effective gluon propagator is obtained by calculating the one-loop gluon self-energies containing the quark, gluon, and ghost loop. The gluon and ghost loops are modified in the presence of the Gribov parameter. We also calculate the decay width from the imaginary part of the potential. We also discuss the medium effect of heavy quark potential with the localized action via auxiliary fields.
12.Deconstructed Hypercharge: A Natural Model of Flavour
Authors:Joe Davighi, Ben A. Stefanek
Abstract: The flavour puzzle is one of the greatest mysteries in particle physics. A `flavour deconstruction' of the electroweak gauge symmetry, by promoting at least part of it to the product of a third family factor (under which the Higgs is charged) times a light family factor, allows one to address the flavour puzzle at a low scale due to accidentally realised $U(2)^5$ flavour symmetries. The unavoidable consequence is new heavy gauge bosons with direct couplings to the Higgs, threatening the stability of the electroweak scale. In this work, we propose a UV complete model of flavour based on deconstructing only hypercharge. We find that the model satisfies finite naturalness criteria, benefiting from the smallness of the hypercharge gauge coupling in controlling radiative Higgs mass corrections and passing phenomenological bounds. Our setup allows one to begin explaining flavour at the TeV scale, while dynamics solving the large hierarchy problem can lie at a higher scale up to around 10 TeV - without worsening the unavoidable little hierarchy problem. The low-energy phenomenology of the model is dominated by a single $Z'$ gauge boson with chiral and flavour non-universal couplings, with mass as light as a few TeV thanks to the $U(2)^5$ symmetry. The natural parameter space of the model will be probed by the HL-LHC and unavoidably leads to large positive shifts in the $W$-boson mass, as well as an enhancement in $\text{Br}(B_{s,d} \to \mu^+ \mu^-)$. Finally, we show that a future electroweak precision machine such as FCC-ee easily has the reach to fully exclude the model.
13.A Novel Beam-Dump Measurement with the LHC General-Purpose Detectors
Authors:Bhaskar Dutta, Doojin Kim, Hyunyong Kim
Abstract: We propose a novel scheme for performing a beam-dump-like experiment with the general-purpose detectors (ATLAS and CMS) at the LHC. Collisions of high-energy protons result in jets containing a number of energetic hadrons and electromagnetic objects that are essentially "dumped" to hadronic and electromagnetic calorimeters, respectively, and induce the production of secondary hadrons, electrons, and photons in calorimetric showers. We envision a situation where new physics particles are produced by the interactions of these secondary particles inside the calorimeters. For proof of principles, we consider the axion-like particles (ALPs) produced via the Primakoff process in the presence of their interaction with photons at CMS. We argue that the drift tube chambers and the ME0 module of the muon system can serve as detectors to record the photons from the ALP decay, demonstrating that the resulting sensitivity reach is competitive due to their close proximity to the signal source points. We further show that the LHC does not suffer from a barrier, dubbed beam-dump "ceiling", that typical beam-dump experiments hardly surpass, carrying the great potential for exploring a wide range of parameter space in increasing statistics. This analysis can be extended to investigate various types of light mediators with couplings to the Standard Model leptons and quarks.
14.Bremsstrahlung-induced Gravitational Waves in Monomial Potentials during Reheating
Authors:Basabendu Barman, Nicolás Bernal, Yong Xu, Óscar Zapata
Abstract: We discuss the production of primordial gravitational waves (GW) from radiative inflaton decay during the period of reheating, assuming perturbative decay of the inflaton either into a pair of bosons or fermions, leading to successful reheating satisfying constraint from Big Bang nucleosynthesis. Assuming that the inflaton $\phi$ oscillates in a general monomial potential $V(\phi)\propto \phi^n$, which results in a time-dependent inflaton decay width, we show that the resulting stochastic GW background can have optimistic detection prospects, especially in detectors that search for a high-frequency GW spectrum, depending on the choice of $n$ that determines the shape of the potential during reheating. We also discuss how this GW energy density may affect the measurement of $\Delta N_{\text{eff}}$ for bosonic and fermionic reheating scenarios.
15.Power Counting to Saturation
Authors:Iain Stewart, Varun Vaidya
Abstract: We present a description of saturation in small x deep inelastic scattering from power counting in a top-down effective theory derived from QCD. A factorization formula isolates the universal physics of the nucleus at leading power in x. The onset of saturation is then understood as a breakdown in the expansion in an emergent power counting parameter, which is defined by the matrix element of a gauge invariant operator. We demonstrate the presence of a novel collinear-soft radiation mode, which clarifies the role played by the medium size in deciding linear/non-linear evolution of the cross section in $\ln x$.
16.Trinification from $\mathrm{E}_{6}$ symmetry breaking
Authors:K. S. Babu, Borut Bajc, Vasja Susič
Abstract: In the context of $\mathrm{E}_{6}$ Grand Unified Theories (GUTs), an intriguing possibility for symmetry breaking to the Standard Model (SM) group involves an intermediate stage characterized by either $\mathrm{SU}(3)\times\mathrm{SU}(3)\times\mathrm{SU}(3)$ (trinification) or $\mathrm{SU}(6)\times\mathrm{SU}(2)$. The more common choices of $\mathrm{SU(5)}$ and $\mathrm{SO}(10)$ GUT symmetry groups do not offer such breaking chains. We argue that the presence of a real (rank $2$ tensor) representation $\mathbf{650}$ of $\mathrm{E}_{6}$ in the scalar sector is the minimal and likely only reasonable possibility to obtain one of the novel intermediate stages. We analyze the renormalizable scalar potential of a single copy of the $\mathbf{650}$ and find vacuum solutions that support regularly embedded subgroups $\mathrm{SU}(3)\times\mathrm{SU}(3)\times\mathrm{SU}(3)$, $\mathrm{SU}(6)\times\mathrm{SU}(2)$, and $\mathrm{SO}(10)\times\mathrm{U}(1)$, as well as specially embedded subgroups $\mathrm{F}_{4}$ and $\mathrm{SU}(3)\times\mathrm{G}_{2}$ that do not contain the SM gauge symmetry. We show that for a suitable choice of parameters, each of the regular cases can be obtained as the lowest among the analyzed minima in the potential.
17.Novel signals for the Type-X two Higgs doublet scenario at the Large Hadron Collider
Authors:Biswarup Mukhopadhyaya, Sirshendu Samanta, Tousik Samui, Ritesh K. Singh
Abstract: We consider, in the context of the Large Hadron Collider, the signals of the Type-X two Higgs doublet model (2HDM) in the parameter region answering to the best possible solution to the muon $(g-2)$ data within this framework. The analysis takes into account all theoretical and observational constraints, and is based on the final state comprising a same-sign dilepton pair and a pair of same-sign $\tau$ jets. The crucial ingredient in making the signal clean is the same-sign feature of both the dilepton and the $\tau$-jet pair individually. After a detailed estimate of the signal and all noteworthy backgrounds, we show that this channel offers by far the best signal significance among those studied so far, predicting discovery with an integrated luminosity of 3000 fb$^{-1}$, and strong indications even with 1000 fb$^{-1}$ if systematic uncertainies do not exceed about 10%. We also demonstrate that the recently developed dynamic radius jet algorithm is effective in this connection.
18.Model independent analysis of femtoscopic correlation functions: An application to the $D_{s0}^*(2317)$
Authors:Natsumi Ikeno, Genaro Toledo, Eulogio Oset
Abstract: We face the inverse problem of obtaining the interaction between coupled channels from the correlation functions of these channels. We apply the method to the interaction of the $D^0 K^+$, $D^+ K^0$, and $D^+_s \eta$ channels, from where the $D_{s0}^*(2317)$ state emerges. We use synthetic data extracted from an interaction model based on the local hidden gauge approach and find that the inverse problem can determine the existence of a bound state of the system with a precision of about 5 MeV. At the same time, we can determine the isospin nature of the bound state and its compositeness in terms of the channels. Furthermore, we evaluate the scattering length and effective range of all three channels, as well as the couplings of the bound state found to all the components. Lastly, the size parameter of the source function, $R$, which in principle should be a magnitude provided by the experimental teams, can be obtained from a fit to the data with a high accuracy. These findings show the value of the correlation function to learn about the meson-meson interaction for systems which are difficult to access in other present facilities.
1.Two-pole structure of the $b_1$(1235) axial-vector meson
Authors:Samson Clymton, Hyun-Chul Kim
Abstract: We investigate the dynamical generation of the $b_1$ meson in the $\pi\omega$ interaction, using the fully off-mass-shell coupled-channel formalism with the $\pi\omega$, $\eta\rho$, $\pi\phi$, and $K\bar{K}^*$ channels included. We first construct the Feynman amplitudes for the sixteen different kernel amplitudes, considering only the $t$ and $u$ channels. Solving the coupled integral equation, we obtain the transition amplitude for the $\pi\omega$ interaction. We select the axial-vector and isovector channels from the partial-wave expansion and single out the two poles corresponding to the $b_1$ mesons: $(1306-i70)$ MeV and $(1356-i65)$ MeV. They are located below the $K\bar{K}^*$ threshold. The first pole lies below the $\eta\rho$ threshold by about 10 MeV, whereas the second one emerges above it by about 40 MeV. We analyze the effects of the two poles and background contributions to the $\pi\omega$ total cross section by using a toy model.
2.A global analysis for determined and undetermined hadronic two body weak decays of anti-triplet charmed baryons
Authors:Zhi-Peng Xing, Xiao-Gang He, Fei Huang, Chang Yang
Abstract: A large amount of data on hadronic two body weak decays of anti-triplet charmed baryons $T_{c\bar 3}$ to an octet baryon $T_8$ and an octet or singlet pseudoscalar meson $P$, $T_{c \bar 3} \to T_8 P$, have been measured. The SU(3) flavor symmetry has been applied to study these decays to obtain insights about weak interactions for charm physics. However not all such decays needed to determine the SU(3) irreducible amplitudes have been measured forbidding a complete global analysis. Previously, it has been shown that data from measured decays can be used to do a global fit to determine all except one parity violating and one parity conserving amplitudes of the relevant SU(3) irreducible amplitudes causing 8 hadronic two body weak decay channels involving $\Xi^0_c$ to $\eta$ or $\eta'$ transitions undetermined. It is important to obtain information about these decays in order to guide experimental searches. In this work using newly measured decay modes by BESIII and Belle in 2022, we carry out a global analysis and parameterize the unknown amplitudes to provide the ranges for the branching ratios of the 8 undetermined decays. Our results indicate that the SU(3) flavor symmetry can explain the measured data exceptionally well, with a remarkable minimal $\chi^2/d.o.f.$ of 1.21 and predict 80 observables in 45 decays for future experimental data to test. We then vary the unknown SU(3) amplitudes to obtain the allowed range of branching ratios for the 8 undetermined decays. We find that some of them are within reach of near future experimental capabilities. We urge our experimental colleagues to carry out related searches.
3.Structure of the medium formed in heavy ion collisions
Authors:J. R. Alvarado García, D. Rosales Herrera, A. Fernández Téllez, Bogar Díaz, J. E. Ramírez
Abstract: We investigate the structure of the medium formed in heavy ion collisions using three different models: the Color String Percolation Model (CSPM), the Core-Shell-Color String Percolation Model (CSCSPM), and the Color Glass Condensate (CGC) framework. We analyze the radial distribution function of the transverse representation of color flux tubes in each model to determine the medium's structure. Our results indicate that the CSPM behaves as an ideal gas, while the CSCSPM exhibits a structural phase transition from a gas-like to a liquid-like structure. Additionally, our analysis of the CGC framework suggests that it produces systems that behave like interacting gases for AuAu central collisions at RHIC energies and liquid-like structures for PbPb central collisions at LHC energies.
4.Study of anomalous $W^-W^+γ/Z$ couplings using polarizations and spin correlations in $e^-e^+\to W^-W^+$ with polarized beams
Authors:Amir Subba, Ritesh K. Singh
Abstract: We study the anomalous $W^-W^+\gamma/Z$ couplings in $e^-e^+\to W^-W^+$ followed by semileptonic decay using a complete set of polarization and spin correlation observables of $W$ boson with the longitudinally polarized beam. We consider a complete set of dimension-six operators affecting $W^-W^+\gamma/Z$ vertex, which are $SU(2)\times U(1)$ gauge invariant. Some of the polarization and spin correlation asymmetries average out if the daughter of $W^+$ is not tagged. We developed an artificial neural network and boosted decision trees to distinguish down-type jets from up-type jets. We obtain bounds on the anomalous couplings for center of mass energy $\sqrt{s} = 250$ GeV with integrated luminosities of~$\mathcal{L}\in\{100~\text{fb}^{-1}, 250~\text{fb}^{-1}, 1000~\text{fb}^{-1}, 3000~\text{fb}^{-1}\}$. We find that using spin-related observables and cross~section in the presence of initial beam polarization significantly improves the bounds on anomalous couplings compared to previous studies.
5.Bilinear R-parity violating supersymmetry under the light of neutrino oscillation, higgs and flavor data
Authors:Arghya Choudhury, Sourav Mitra, Arpita Mondal, Subhadeep Mondal
Abstract: In this work, we explore a well motivated beyond the Standard Model scenario, namely, R-parity violating Supersymmetry, in the context of light neutrino masses and mixing. We assume that the R-parity is only broken by the lepton number violating bilinear term. We try to fit two non-zero neutrino mass square differences and three mixing angle values obtained from the global $\chi^2$ analysis of neutrino oscillation data. We have also taken into account the updated data of the standard model (SM) Higgs mass and its coupling strengths with other SM particles from LHC Run-II along with low energy flavor violating constraints like rare b-hadron decays. We have used a Markov Chain Monte Carlo (MCMC) analysis to constrain the new physics parameter space. While doing so, we ensure that all the existing collider constraints are duly taken into account. Through our analysis we have derived the most stringent constraints possible till date with existing data on the 9 bilinear R-parity violating parameters along with $\mu$ and $\tan\beta$. We further explore the possibility of explaining the anomalous muon (g - 2) measurement staying within the parameter space allowed by neutrino, Higgs and flavor data while satisfying the collider constraints as well. We find that there still remains a small sub-TeV parameter space where the required excess can be obtained.
6.Production of Excited Doubly Heavy Baryons at the Super-$Z$ Factory
Authors:Juan-Juan Niu, Jing-Bo Li, Huan-Yu Bi, Hong-Hao Ma
Abstract: In the framework of nonrelativistic QCD, the $P$-wave excited doubly heavy baryons are thoroughly studied via the channel $e^{+} e^{-}\rightarrow \langle QQ^{\prime}\rangle[n] \rightarrow \Xi_{QQ^{\prime}} +\bar{Q^{\prime}} +\bar{Q}$, which takes place at the collision energy $Z$-pole. $Q^{(\prime)}$ represents $b$ or $c$ quark for the production of $\Xi_{cc}$, $\Xi_{bc}$, and $\Xi_{bb}$, respectively. All of the intermediate diquark states $\langle QQ'\rangle[n]$ in $P$-wave, $\langle cc\rangle[^{1}P_{1}]_{\mathbf{\bar 3}}$, $\langle cc\rangle[^{3}P_{J}]_{\mathbf{6}}$, $\langle bc\rangle[^{1}P_{1}]_{\mathbf{\bar 3}/ \mathbf{6}}$, $\langle bc\rangle[^{3}P_{J}]_{\mathbf{\bar 3}/ \mathbf{6}}$, $\langle bb \rangle[^{1}P_{1}]_{\mathbf{\bar 3}}$, and $\langle bb\rangle[^{3}P_{J}]_{\mathbf{6}}$ with $J=0$, 1, or 2, are taken into account. The cross sections and differential distributions, including the transverse momentum, rapidity, angular, and invariant mass, are discussed for the excited baryons production. The result is that the contributions of $\Xi_{cc}$, $\Xi_{bc}$, and $\Xi_{bb}$ in $P$-wave are found to be 3.97$\%$, 5.08$\%$, and 5.89$\%$, respectively, compared to $S$-wave. Supposing that all $P$-wave excited states can decay into the ground state 100\%, the total events $N_{\Xi_{cc}}=8.48 \times10^{4-6}$, $N_{\Xi_{bc}}=2.26\times10^{5-7}$, and $N_{\Xi_{bb}}=4.12 \times10^{3-5}$ would be produced at the Super-$Z$ Factory with a high luminosity up to ${\cal L} \simeq 10^{34-36}{\rm cm}^{-2} {\rm s}^{-1}$.
7.Extraction of the $x$-dependence of generalized parton distributions from exclusive photoproduction
Authors:Jian-Wei Qiu, Zhite Yu
Abstract: The $x$-dependence of hadrons' generalized parton distributions (GPDs) $\mathcal{F}(x,\xi,t)$ is the most difficult to extract from the existing known processes, while the $\xi$ and $t$ dependence are uniquely determined by the kinematics of the scattered hadron. We study the single diffractive hard exclusive processes for extracting GPDs in the photoproduction. We demonstrate quantitatively the enhanced sensitivity on extracting the $x$-dependence of various GPDs from the photoproduction cross sections, as well as the asymmetries constructed from photon polarization and hadron spin that could be measured at JLab Hall D by GlueX Collaboration and future facilities.
1.Sharpening the $A\to Z^{(*)}h $ Signature of the Type-II 2HDM at the LHC through Advanced Machine Learning
Authors:W. Esmail, A. Hammad, S. Moretti
Abstract: The $A\to Z^{(*)}h$ decay signature has been highlighted as possibly being the first testable probe of the Standard Model (SM) Higgs boson discovered in 2012 ($h$) interacting with Higgs companion states, such as those existing in a 2-Higgs Doublet Model (2HDM), chiefly, a CP-odd one ($A$). The production mechanism of the latter at the Large Hadron Collider (LHC) takes place via $b\bar b$-annihilation and/or $gg$-fusion, depending on the 2HDM parameters, in turn dictated by the Yukawa structure of this Beyond the SM (BSM) scenario. Among the possible incarnations of the 2HDM, we test here the so-called Type-II, for a twofold reason. On the one hand, it intriguingly offers two very distinct parameter regions compliant with the SM-like Higgs measurements, i.e., where the so-called `SM limit' of the 2HDM can be achieved. On the other hand, in both configurations, the $AZh$ coupling is generally small, hence the signal is strongly polluted by backgrounds, so that the exploitation of Machine Learning (ML) techniques becomes extremely useful. Ours approach in this respect is a three-prong one. Firstly, we adjust ML models to analyze all possible High Energy Physics (HEP) data types, so as to maximize the amount of input information. Secondly, unlike most `black-box' ML approaches currently in use in the HEP community, we exploit a (linear) Centered Kernel Alignment (CKA) similarity metric to analyze the learned representations in the hidden layers, thereby enabling an interpretative element of our results. Thirdly, we emphasise that the proposed ML models are generic and can thus be adopted in other physics problems. Concerning the one at hand, by using such advanced ML implementations, we ultimately show that the sensitivity of LHC searches in the $l^+l^- b\bar b$ ($l=e,\mu$) final state can significantly be improved with respect to traditional cut-and-count analyses and/or, etc
2.Electroweak Loop Contributions to the Direct Detection of Wino Dark Matter
Authors:John Ellis, Natsumi Nagata, Keith A. Olive, Jiaming Zheng
Abstract: Electroweak loop corrections to the matrix elements for the spin-independent scattering of cold dark matter particles on nuclei are generally small, typically below the uncertainty in the local density of cold dark matter. However, as shown in this paper, there are instances in which the electroweak loop corrections are relatively large, and change significantly the spin-independent dark matter scattering rate. An important example occurs when the dark matter particle is a wino, e.g., in anomaly-mediated supersymmetry breaking (AMSB) and pure gravity mediation (PGM) models. We find that the one-loop electroweak corrections to the spin-independent wino LSP scattering cross section generally interfere constructively with the tree-level contribution for AMSB models with negative Higgsino mixing, $\mu < 0$, and in PGM-like models for both signs of $\mu$, lifting the cross section out of the neutrino fog and into a range that is potentially detectable in the next generation of direct searches for cold dark matter scattering.
3.Correlating New Physics Effects in Semileptonic $ΔC = 1$ and $ΔS = 1$ Processes
Authors:Svjetlana Fajfer, Jernej Fesel Kamenik, Arman Korajac, Nejc Košnik
Abstract: We present constraints on the left-handed dimension-6 interactions that contribute to semileptonic and leptonic decays of $K$, $D$, pions and to nuclear beta decay. We employ the flavour covariant description of the effective couplings, identify universal CP phases of New Physics and derive constraints from decay rates and CP-odd quantities. As a result, we can predict the maximal effects of such flavoured NP in $D$ decays from stringent $K$ decay constraints and vice-versa.
4.Holographic study of higher-order baryon number susceptibilities at finite temperature and density
Authors:Zhibin Li, Jingmin Liang, Song He, Li Li
Abstract: The cumulants of baryon number fluctuations serve as a good probe for experimentally exploring the QCD phase diagram at finite density, giving rise to characteristic fluctuation patterns associated with a possible critical endpoint (CEP). We compute the higher-order baryon number susceptibilities at finite temperature and baryon chemical potential using a holographic QCD model to address the non-perturbative aspect of strongly coupled QCD matter. The model can accurately confront lattice QCD data on a quantitative level and the location of the CEP is found to fall within the range accessible to upcoming experimental measurements. The baryon number susceptibilities up to the twelfth order are computed, and the collision energy dependence of different ratios of these susceptibilities is examined along the chemical freeze-out line. The holographic results show quantitative agreement with experimental data and the functional renormalization group results in a large collision energy range, with all ratios exhibiting a peak structure around 5-10 GeV. The mismatching between our holographic results with experimental data for sufficiently low collision energy is possibly due to non-equilibrium effects and complex experimental environments. The future experiments with measurements in the low collision energy range $\sqrt{S_{NN}}\approx 1-10~\text{GeV}$ and reduced experimental uncertainty could reveal more non-monotonic behavior signals which can be used to locate the CEP.
5.Effect of nuclear structure on particle production in relativistic heavy-ion collisions using the AMPT model
Authors:P. Sinha, V. Bairathi, K. Gopal, C. Jena, S. Kabana
Abstract: We report first study of transverse momentum ($p_\mathrm{T}$) spectra for $\pi^{\pm}$, $K^{\pm}$, $p$, and $\bar{p}$ in isobar, $^{96}_{44}$Ru+$^{96}_{44}$Ru and $^{96}_{40}$Zr+$^{96}_{40}$Zr, collisions at $\sqrt{s_{\mathrm{NN}}} = 200$ GeV using a multi-phase transport (AMPT) model. Particle yields ($dN/dy$), average transverse momenta ($\langle p_\mathrm{T} \rangle$), and particle ratios are reported in various collision systems with different parameterizations of the Woods-Saxon (WS) distribution. We observed a maximum difference of 5% in the particle yields in peripheral collisions when we included a quadrupole and octupole deformation and a nuclear size difference between the isobars. The $\pi^{-}$/$\pi^{+}$ ratio is smaller in Ru+Ru collisions compared to Zr+Zr collisions indicating an effect of isospin due to difference in number of protons and neutrons between the two nuclei. The $K^{-}$/$K^{+}$ ratio is same in both the systems indicating the dominance of the pair production mechanism in the kaon production. The $\bar{p}/p$ ratio is further smaller in Ru+Ru collisions than Zr+Zr collisions, indicating the effect of baryon stopping in addition to the isospin effect. A system size dependence is observed in $dN/dy$ and $\langle p_\mathrm{T} \rangle$ when we compare the results from isobar collisions with Au+Au and U+U collisions.
6.Effects of gluon kinematics and the Sudakov form factor on the dipole amplitude
Authors:Tomoki Goda, Krzysztof Kutak, Sebastian Sapeta
Abstract: We investigate effects of exact gluon kinematics on the parameters of the Golec-Biernat-W\"usthoff, and Bartels-Golec-Biernat-Kowalski saturation models. The resulting fits show some differences, particularly, in the normalization of the dipole cross section $\sigma_0$. The refitted models are used for the dijet production process in DIS to investigate effects of the Sudakov form factor at Electron Ion Collider energies.
7.Oblique corrections when $m_W \neq m_Z \cos{θ_W}$ at tree level
Authors:Simonas Draukšas, Vytautas Dūdėnas, Luís Lavoura
Abstract: The parametrization of the oblique corrections through $S$, $T$, and $U$ -- later extended by $V$, $W$, and $X$ -- is a convenient way of comparing the predictions for various electroweak observables at the one-loop level between the Standard Model and its extensions. That parametrization assumes that the extensions under consideration have ${SU(2)\times U(1)}$ gauge symmetry \emph{and} the tree-level relation $m_W = m_Z \cos{\theta_W}$ between the Weinberg angle and the gauge-boson masses. In models where that relation does not hold at the Lagrangian level, the parameter $T$ is not ultraviolet-finite, making the parametrization inadequate. We present expressions that parametrize the difference of the various predictions of two models with $m_W \neq m_Z \cos{\theta_W}$ in terms of oblique parameters. The parameter $T$ does not play a role in those expressions. Conveniently, they may be reached, from the ones that were derived for models with tree-level $m_W = m_Z \cos{\theta_W}$, by performing a simple substitution for $T$. We also discuss the difficulties in using oblique parameters when comparing a model with $m_W \neq m_Z \cos{\theta_W}$ to the Standard Model. Finally, we compute the relevant five oblique parameters in the SM extended by scalars in both $Y=0$ and $Y=1$ triplets.
8.Goodness of fit by Neyman-Pearson testing
Authors:Gaia Grosso, Marco Letizia, Maurizio Pierini, Andrea Wulzer
Abstract: The Neyman-Pearson strategy for hypothesis testing can be employed for goodness of fit if the alternative hypothesis $\rm H_1$ is generic enough not to introduce a significant bias while at the same time avoiding overfitting. A practical implementation of this idea (dubbed NPLM) has been developed in the context of high energy physics, targeting the detection in collider data of new physical effects not foreseen by the Standard Model. In this paper we initiate a comparison of this methodology with other approaches to goodness of fit, and in particular with classifier-based strategies that share strong similarities with NPLM. NPLM emerges from our comparison as more sensitive to small departures of the data from the expected distribution and not biased towards detecting specific types of anomalies while being blind to others. These features make it more suited for agnostic searches for new physics at collider experiments. Its deployment in other contexts should be investigated.
9.On the Dirac-Majorana neutrinos distinction in four-body decays
Authors:Juan Manuel Márquez, Diego Portillo-Sánchez, Gabriel López Castro, Pablo Roig
Abstract: Motivated by the novel method discussed in arXiv:2106.11785 to differentiate the effects of Dirac and Majorana neutrinos in four-body decays, we propose to analyse radiative leptonic lepton-decays ($\ell\to\ell'\nu\bar{\nu}\gamma$), as an independent alternative process to study the possible Majorana nature of neutrinos. Following arXiv:2106.11785, the back-to-back kinematic scenario (for the $\ell'- \gamma$ and $\nu-\bar{\nu}$ systems, respectively) supposedly avoids the constraint imposed by the "practical Dirac-Majorana confusion theorem", as one does not need to fully integrate over neutrino and antineutrino momenta. Our results show that, in this special kinematic configuration, the difference between Dirac and Majorana cases vanishes once the inaccessible neutrino angle is integrated out, which seems to be incompatible with the proposal in arXiv:2106.11785. We work on that and conclude that the discrepancy comes from the kinematic treatment, specifically from the angular integration and clarify these issues with consistency tests. All this applies in absence of non-standard interactions, which can enhance generally the sensitivity to the neutrino nature.
10.QED corrections to parton distributions and Altarelli-Parisi splitting functions in the polarized case
Authors:Daniel de Florian, Lucas Palma Conte
Abstract: We discuss the effect of QED corrections in the evolution of polarized parton distributions. We solve the corresponding evolution equations exactly to ${\cal O}(\alpha )$ and ${\cal O}(\alpha_s^2)$ in Mellin $N$-space, extending the available techniques for pure QCD evolution. To accomplish this, we introduce, for the first time, the Altarelli-Parisi polarized kernels at LO in QED. Furthermore, we perform a phenomenological analysis of the QED effects on polarized parton distributions (pPDFs), proposing different scenarios for the polarized photon density. Finally, we quantify the impact of the corresponding QED contributions to the polarized structure function $g_1$. We show that the relative corrections to both the pPDFs and the $g_1$ structure function are approximately at the few percent level, which is the order of magnitude expected considering the value of $\alpha$.
11.Axion Poltergeist
Authors:Keisuke Harigaya, Keisuke Inomata, Takahiro Terada
Abstract: Rotations of axion fields in the early universe can produce dark matter and the matter-antimatter asymmetry of the universe. We point out that the rotation can generate an observable amount of a stochastic gravitational-wave (GW) background. It can be doubly enhanced in a class of models in which the equation of state of the rotations rapidly changes from a non-relativistic matter-like one to a kination-like one by 1) the so-called Poltergeist mechanism and 2) slower redshift of GWs compared to the axion kination fluid. In supersymmetric UV completion, future GW observations can probe the supersymmetry-breaking scale up to $10^7\,$GeV even if the axion does not directly couple to the Standard Model fields.
12.Reheating process in the $R^2$ inflationary model with the baryogenesis scenario
Authors:Hyun Jeong, Kohei Kamada, Alexei A. Starobinsky, Jun'ichi Yokoyama
Abstract: Post-inflationary evolution and (re)heating of the viable inflationary model, the $R^2$ one, is made more realistic by including the leptogenesis scenario into it. For this purpose, right-handed Majorana neutrinos with a large mass are added to the matter sector of the Standard Model to explain the neutrino oscillation experiments and the baryon asymmetry of the Universe. We have found parameters that characterize this model: non-minimal coupling of the Higgs field $\xi$ and the mass of the right-handed Majorana neutrino $M_{N_\alpha}$. We have analyzed the effect of these parameters on the reheating process and the resultant physical quantities: spectral indices and baryon asymmetry.
13.Vector quarkonia at the LHC with JETHAD: A high-energy viewpoint
Authors:Francesco Giovanni Celiberto
Abstract: In this review we discuss and extend the study of the inclusive production of vector quarkonia, $J/\psi$ and $\Upsilon$, emitted with large transverse momenta and rapidities at the LHC. We adopt the novel ZCW19$^+$ determination to depict the quarkonium production mechanism at the next-to-leading level of perturbative QCD. This approach is based on the nonrelativistic QCD formalism well adapted to describe the production of a quarkonium state from the collinear fragmentation of a gluon or a constituent heavy quark at the lowest energy scale. We rely upon the NLL/NLO$^+$ hybrid high-energy and collinear factorization for differential cross sections, where the standard collinear formalism is enhanced by the BFKL resummation of next-to-leading energy logarithms arising in the $t$-channel. We employ the JETHAD method to analyze the behavior of rapidity distributions for double inclusive vector-quarkonium and inclusive vector-quarkonium plus jet emissions. We discovered that the natural stability of the high-energy series, previously observed in observables sensitive to the emission of hadrons with heavy flavor detected in the rapidity acceptance of LHC barrel calorimeters, becomes even more manifest when these particles are tagged in forward regions covered by endcaps. Our findings brace the important message that vector quarkonia at the LHC via the hybrid factorization offer a unique chance to perform precision studies of high-energy QCD, as well as an intriguing opportunity to shed light on the quarkonium production puzzle.
1.Global Symmetries and Effective Potential of 2HDM in Orbit Space
Authors:Qing-Hong Cao, Kun Cheng, Changlong Xu
Abstract: We extend the framework of analyzing the 2HDM in its orbit space to study the one-loop effective potential before and after electroweak symmetry breaking. In this framework, we present a comprehensive analysis of global symmetries of the one-loop thermal effective potential in the 2HDM, demonstrating when the global symmetries of the tree-level 2HDM potential are broken by loop contributions. By introducing light-cone coordinates and generalizing the bilinear notation around the vacuum, we present a geometric view of the scalar mass matrix and on-shell renormalization conditions.
2.Precision test of the muon-Higgs coupling at a high-energy muon collider
Authors:Jürgen Reuter
Abstract: Muon colliders offer the possibility to go to very high energies with relatively small circular colliders, energies up to 10 or 14 TeV are envisioned. Due to their very clean collider environment they provide a fantastic tool to search for new physics in the electroweak sector, especially through the production of multiple EW vector and Higgs bosons, and they allow to measure the Higgs-muon coupling very precisely. I will elucidate the physics capabilities from these processes and also discuss issues on precision predictions for SM backgrounds at high-energy lepton colliders.
3.Non-factorizable virtual corrections to Higgs boson production in weak boson fusion beyond the eikonal approximation
Authors:Ming-Ming Long, Kirill Melnikov, Jérémie Quarroz
Abstract: Non-factorizable virtual corrections to Higgs boson production in weak boson fusion at next-to-next-to-leading order in QCD were estimated in the eikonal approximation [1]. This approximation corresponds to the expansion of relevant amplitudes around the forward limit. In this paper we compute the leading power correction to the eikonal limit and show that it is proportional to first power of the Higgs boson transverse momentum or the Higgs boson mass over partonic center-of-mass energy. Moreover, this correction can be significantly enhanced by the rapidity of the Higgs boson. For realistic weak boson fusion cuts, the next-to-eikonal correction reduces the estimate of non-factorizable contributions to fiducial cross section by O(30) percent.
4.Simulations of laser-driven strong-field QED with Ptarmigan: Resolving wavelength-scale interference and $γ$-ray polarization
Authors:T. G. Blackburn, B. King, S. Tang
Abstract: Accurate modelling is necessary to support precision experiments investigating strong-field QED phenomena. This modelling is particularly challenging in the transition between the perturbative and nonperturbative regimes, where the normalized laser amplitude $a_0$ is comparable to unity and wavelength-scale interference is significant. Here we describe how to simulate nonlinear Compton scattering, Breit-Wheeler pair creation, and trident pair creation in this regime, using the Monte Carlo particle-tracking code Ptarmigan. This code simulates collisions between high-intensity lasers and beams of electrons or $\gamma$ rays, primarily in the framework of the locally monochromatic approximation (LMA). We benchmark our simulation results against full QED calculations for pulsed plane waves and show that they are accurate at the level of a few per cent, across the full range of particle energies and laser intensities. This work extends our previous results to linearly polarized lasers and arbitrarily polarized $\gamma$ rays.
5.Breakup Corrections to Spin Asymmetries in the $^3$He Beam Polarization Measurement with HJET
Authors:Andrei Poblaguev
Abstract: The requirements for hadron polarimetry at the future Electron Ion Collider (EIC) include measurements of the absolute helion ($^3$He, $h$) beam polarization with systematic uncertainties better than $\sigma^\text{syst}_P/P\le1\%$. Recently, it was proposed that the Polarized Atomic Hydrogen Gas Jet Target (HJET) be utilized for the precision measurement of the polarization of the $\sim$100 GeV/n helion beam. At the Relativistic Heavy Ion Collider, HJET serves to determine the absolute proton beam polarization with low systematic uncertainties of about $\delta^\text{syst}P/P\lesssim0.5\%$. To adapt the HJET method for the EIC helion beam, the experimentally determined ratio of the beam and target (jet) spin-correlated asymmetries should be adjusted by the ratio of $p^\uparrow{h}$ and $h^\uparrow{p}$ analyzing powers. A potential problem with the suggested method is that the breakup of $^3$He in polarization measurements could drastically affect the analyzing power ratio. However, an analysis of the breakup corrections, presented in this paper, reveals that while these corrections can be as substantial as $\sim$4\%, the effect cancels out to a negligible level in the measured beam polarization.
6.The chiral magnetic effect in a cylindrical domain
Authors:Matteo Buzzegoli, Kirill Tuchin
Abstract: We compute the Chiral Magnetic Effect (CME) in a cylindrical region coaxial with the external magnetic field. As the boundary condition we require vanishing of the radial component of the electric current on the cylinder side wall. We find that when the magnetic length is comparable or larger than the cylinder radius, the CME is suppressed compared to the corresponding result in infinite medium. As a result, for a given cylinder radius, the suppression is stronger in weak fields. We argue that the electric current generated by the CME vanishes at the cylinder wall and monotonically increases towards the symmetry axis.
7.Production of bottomonia states in proton+proton and heavy-ion collisions
Authors:Vineet Kumar, Prashant Shukla, Abhijit Bhattacharyya
Abstract: In this work, we review the experimental and theoretical developments of bottomonia production in proton+proton and heavy-ion collisions. The bottomonia production process is proving to be one of the most robust processes to investigate the fundamental aspects of Quantum Chromodynamics at both low and high temperatures. The LHC experiments in the last decade have produced large statistics of bottomonia states in wide kinematic ranges in various collision systems. The bottomonia have three $\Upsilon$ S-states which are reconstructed in dilepton invariant mass channel with high mass resolution by LHC detectors and P-states are measured via their decay to S-states. We start with the details of measurements in proton+proton collisions and their understanding in terms of various effective theoretical models. Here we cover both the Tevatron and LHC measurements with $\sqrt{s}$ spanning from 1.8 TeV to 13 TeV. The bottomonia states have particularly been very good probes to understand strongly interacting matter produced in heavy-ion collisions. The Pb+Pb collisions have been performed at $\sqrt{s_{NN}}$ = 2.76 TeV and 5.02 TeV at LHC. This led to the detailed study of the modification of bottomonia yields as a function of various observables and collision energy. At the same time, the improved results of bottomonia production became available from RHIC experiments which have proven to be useful for a quantitative comparison. A systematic study of bottomonia production in p+p, p+Pb and Pb+Pb has been very useful to understand the medium effects in these collision systems. We review some of the (if not all the) models of bottomonia evolution due to various processes in a large dynamically evolving medium and discuss these in comparison with the measurements.
8.Inconsistencies in and short pathlength correction to $R_{AA}(p_T)$ in $\mathrm{A}+\mathrm{A}$ and $\mathrm{p} + \mathrm{A}$ collisions
Authors:Coleridge Faraday, Antonia Grindrod, W. A. Horowitz
Abstract: We present the first leading hadron suppression predictions in $\mathrm{Pb}+\mathrm{Pb}$ and $\mathrm{p}+\mathrm{Pb}$ collisions from a convolved radiative and collisional energy loss model in which partons propagate through a realistic background and in which the inelastic energy loss receives a short pathlength correction. We find that the short pathlength correction is small for $D$ and $B$ meson $R_{AA}(p_T)$ in both $\mathrm{Pb}+\mathrm{Pb}$ and $\mathrm{p}+\mathrm{Pb}$ collisions. However the short pathlength correction leads to a surprisingly large reduction in suppression for $\pi$ mesons in $\mathrm{p}+\mathrm{Pb}$ and even $\mathrm{Pb}+\mathrm{Pb}$ collisions. We systematically check the consistency of the assumptions used in the radiative energy loss derivation$\unicode{x2014}$such as collinearity, softness, and large formation time$\unicode{x2014}$with the final numerical model. While collinearity and softness are self-consistently satisfied in the final numerics, we find that the large formation time approximation breaks down at modest to high momenta $p_T \gtrsim 30$ GeV. We find that both the size of the small pathlength correction to $R_{AA}(p_T)$ and the $p_T$ at which the large formation time assumption breaks down are acutely sensitive to the chosen distribution of scattering centers in the plasma.
9.Conserved charge fluctuations in the relativistic mean-field hadron resonance gas model: constraints on hadronic repulsive interactions
Authors:Somenath Pal, Guruprasad Kadam, Abhijit Bhattacharyya
Abstract: We investigate the effect of repulsive interaction between hadrons on the susceptibilities of conserved charges, namely baryon number (B), electric charge (Q) and strangeness (S). We estimate second and fourth-order susceptibilities of conserved charges, their differences, ratios and correlations within the ambit of the mean-field hadron resonance gas (MFHRG) model. We consider repulsive mean-field interaction among meson pairs, anti-meson pairs, baryon pairs and anti-baryon pairs separately and constrain them by confronting MFHRG results of various susceptibilities with the recent lattice QCD (LQCD) data. We find that the repulsive interactions between baryon-baryon pairs and antibaryon-antibaryon pairs are sufficient to describe the thermodynamics of hadronic matter at temperatures below the QCD transition temperature. Very weak mesonic repulsive interaction is needed only to describe electric charge susceptibilities and can be neglected in the description of other susceptibilities. We finally conclude that the repulsive interaction between hadrons plays a very important role in describing the thermodynamic properties of hadronic matter, especially near quark-hadron phase transition temperature ($T_c$). The mean-field parameter for baryons ($K_B$) should be constrained to the range $0.40\le K_B\le 0.450$ $\text{GeV.fm}^{3}$ to get a good agreement with the LQCD results.
1.Chiral anomaly in a (1+1)-dimensional Floquet system under high-frequency electric fields
Authors:Kenji Fukushima, Yoshimasa Hidaka, Takuya Shimazaki, Hidetoshi Taya
Abstract: We investigate the chiral anomaly in a Floquet system under a time-periodic electric field in (1+1) dimensions. Using the van~Vleck high-frequency expansion, we analytically quantify how the topological charge is equated with the chirality production and the pseudo-scalar condensate for massive fermions. In the high-frequency limit, we find that finite-mass effects are suppressed and the topological charge is dominated by the chirality production. Our calculations show that the information about the chiral anomaly is stored not in the static Floquet Hamiltonian but in the periodic kick operator. The computational steps are useful as the theoretical foundation for higher-dimensional generalization.
2.Nuclear effects in extracting $\sin^2θ_W$ and a probe for short-range correlations
Authors:Xing-Hua Yang, Fei Huang, Ji Xu
Abstract: We investigate the neutral-current neutrino-nucleon deep inelastic scattering with particular emphasis on short-range correlation and EMC effect, as well as their impact on the weak-mixing angle $\sin^2\theta_W$ determination. The ratios of structure function $F_{2(NC)}^{A}$ and $x F_{3(NC)}^{A}$ are presented where the nuclei $A$ are chosen as carbon, iron and lead. One kind of universal modification function is proposed which would provide a nontrivial test of SRC universality on the platform of neutrino-nucleon DIS. In addition, we study the impact of ``SRC-driven'' nuclear effects on the extraction of $\sin^2\theta_W$ which is naturally associated with the renowned NuTeV anomaly. The results indicate that these effects may account for a substantial fraction of the NuTeV anomaly and considerably affect the value of extracted $\sin^2\theta_W$.
3.Extra Dimensions and Physics of Low Scale Strings
Authors:Ignatios Antoniadis, Karim Benakli
Abstract: This review aims to provide a very short and pedestrian introduction to some of the basics of extra-dimensional physics. The hope is to facilitate access and to be, in some respects, complementary to the many already existing reviews on phenomenological applications of extra dimensions in our Universe.
4.Survival Probability of Unstable States in Coupled-Channels -- nonexponential decay of "threshold-cusp"
Authors:Wren A. Yamada, Osamu Morimatsu, Toru Sato, Koichi Yazaki
Abstract: We investigate the survival probability of unstable states, the time-dependence of an initial state, in coupled channels. First, we extend the formulation of the survival probability from single channel to coupled channels (two channels). We derive an exact general expression of the two-channel survival probability using uniformization, a method which makes the coupled-channel S matrix single-valued, and the Mittag-Leffler expansion, i.e. a pole expansion. Second, we calculate the time dependence of the two-channel survival probability by employing the derived expression. It is the minimal distance between the pole and the physical region in the complex energy plane, not the imaginary part of the pole energy, which determines not only the energy spectrum of the Green's function but also the survival probability. The survival probability of the "threshold-cusp" caused by a pole on the unusual complex-energy Riemann sheet is shown to decay, not grow in time though the imaginary part of the pole energy is positive. We also show that the decay of the "threshold-cusp" is non-exponential. Thus, the "threshold-cusp" is shown to be a new type of unstable mode, which is found only in coupled channels.
5.Modified S-wave $ππ$ scattering amplitude for multiparticle PWA
Authors:Igor Kachaev, IHEP
Abstract: Suggested by Au, Morgan, Pennington (AMP) S-wave isospin I=0 $\pi\pi$, $KK$ scattering amplitude is good enough to describe experimental data for the moment. Still it has two disadvantages for use in multiparticle partial wave analysis (PWA), namely sharp drop at the $KK$ threshold and unreasonable behavior at $M(\pi\pi) > 1.6\,GeV/c^2$. The drop is not seen in multiparticle systems. We suggest the modified AMP amplitude, mAMP, for the only aim, namely to describe the broad part of $S$-wave $\pi\pi\,\to\,\pi\pi$ scattering in the wide $M(\pi\pi)$ range in multiparticle PWA. The mAMP amplitude describes threshold behavior of the $\pi\pi\,\to\,\pi\pi$ scattering and the wide structure at $M\sim 1400\,MeV/c^2$ reasonably well. It is assumed that narrow objects $f_0(980)$, $f_0(1500)$ are included in PWA separately. The amplitude does not describe $\pi\pi\to KK$ scattering. The mAMP amplitude is purely phenomenological.
6.Searching for a Heavy Neutral CP-Even Higgs Boson in the BLSSM at the LHC Run 3 and HL-LHC
Authors:M. Ashry, S. Khalil, S. Moretti
Abstract: The detection of a heavy neutral CP-even Higgs boson of the $B-L$ Supersymmetric Standard Model (BLSSM), $h'$, with $m_{h'}\simeq 400~\text{GeV}$, at the Large Hadron Collider (LHC) for a center-of-mass energy of $\sqrt{s}=14~\text{TeV}$, is investigated. The following production and decay channels are considered: $gg\to h'\to{ZZ}\to4\ell$ and $gg\to h'\to{W^+W^-}\to2\ell+\slashed{E}_T$ (with $\slashed{E}_T$ being the Missing~Transverse~Energy~(MET)), where $\ell=e,\mu$, with integrated luminosity $L_{\text{int}}=300~{\text{fb}}^{-1}$ (Run 3). Furthermore, we also look into the di-Higgs channel $gg\to h'\to{hh}\to{b\bar{b}\gamma\gamma}$ at the High-Luminosity LHC (HL-LHC) with an integrated luminosity of $L_{\text{int}}=3000~{\text{fb}}^{-1}$. We demonstrate that promising signals with high statistical significance can be obtained through the three aforementioned channels.
7.Higgs boson production at next-to-leading logarithmic accuracy
Authors:Francesco Giovanni Celiberto, Michael Fucilla, Dmitry Yu. Ivanov, Mohammed M. A. Mohammed, Alessandro Papa
Abstract: It has been recently argued that the inclusive hadroproduction at the LHC of a Higgs boson in association with a jet can be sensitive to the high-energy dynamics. Moreover, the impact of the resummation at FCC energies is expected to be large also in the inclusive cross section for the main Higgs production channel in proton-proton collisions, namely the gluon fusion. As the energy increases, a pure $k_t$-factorization framework or a collinear-factorization approach supplemented by the high-energy resummation are adequate formalisms to describe these processes. In both cases, the fundamental missing ingredient for a next-to-leading logarithmic description is the Higgs boson impact factor. We present the full next-to-leading result for the forward Higgs impact factor, obtained in the infinite top-mass limit, discussing possible future extensions, such as the calculation of the impact factor in the central rapidity region.
8.Gravitational waves from walls bounded by strings in $SO(10)$ model of pseudo-Goldstone dark matter
Authors:Rinku Maji, Wan-Il Park, Qaisar Shafi
Abstract: We explore the gravitational wave spectrum generated by string-wall structures in an $SO(10)$ ($Spin(10)$) based scenario of pseudo-Goldstone boson dark matter (pGDM) particle. This dark matter candidate is a linear combination of the Standard Model (SM) singlets present in the 126 and 16 dimensional Higgs fields. The Higgs $126$-plet vacuum expectation value (VEV) $\left<126_H\right>$ leaves unbroken the $\mathbb{Z}_2$ subgroup of $\mathbb{Z}_4$, the center of $SO(10)$. Among other things, this yields topologically stable cosmic strings with a string tension $\mu \sim \left<126_H\right>^2$. The subsequent (spontaneous) breaking of $\mathbb{Z}_2$ at a significantly lower scale by the $16$-plet VEV $\left<16_H\right>$ leads to the appearance of domain walls bounded by the strings produced earlier. We display the gravitational wave spectrum for $G \mu$ values varying between $10^{-15}$ and $10^{-9}$ ($\left<126_H\right>\sim 10^{11}$ - $10^{14}$ GeV), and $\left<16_H\right>\sim 0.1$ - $10^3$ TeV range ($G$ denotes Newton's constant.) These predictions can be tested, as we show, by a variety of (proposed) experiments including LISA, ET, CE and others.
9.Test of new physics effects in $\bar{B} \to (D^{(*)}, π) \ell^-\barν_{\ell}$ decays with heavy and light leptons
Authors:Ipsita Ray, Soumitra Nandi
Abstract: We study the $\bar{B}\to D(D^*) \ell^-\bar{\nu}_{\ell}$ decays based on the up-to-date available inputs from experiments and the lattice. First, we review the standard model (SM) predictions of the different observables associated with these decay channels. In the analyses, we consider new physics (NP) effects in the channels with the heavy ($\tau$), as well as the light leptons ($\mu, e$). We have extracted $|V_{cb}|$ along with the new Wilson coefficients (WCs) from the available data on light leptons; the extracted value of $|V_{cb}|$ is $(39.9 \pm 0.7)\times 10^{-3}$. The extracted WCs are zero consistent, but some could be of order $10^{-2}$. Also, we have done the simultaneous analysis of the data in $\bar{B} \to D^{(*)}(\mu^-,e^-)\bar{\nu}$ alongside the inputs on $R(D^{(*)}) = \frac{\Gamma(\bar{B}\to D^{(*)}\tau^-\bar{\nu}_{\tau})}{\Gamma(\bar{B}\to D^{(*)}\ell^-\bar{\nu}_{\ell})}$ and the $D^*$ longitudinal polarisation fraction $F_L^{D^*}$ in different NP scenarios and extracted $|V_{cb}|$ which is consistent with the number mentioned above. Also, the simultaneous explanation of $R(D^{(*)})$ and $F_L^{D^*}$ is not possible in the one-operator scenarios. However, the two operator scenarios with $\mathcal{O}_{S_2}^{\tau} = (\bar{q}_R b_L)(\bar{\tau}_R\nu_{\tau L})$ as one of the operators could explain all these three measurements. Finally, we have given predictions of all the related observables in $\bar{B} \to D^{(*)}(\tau^-,\mu^-,e^-)\bar{\nu}$ decays in the NP scenarios, which could be tested in future experiments. We have repeated this exercise for $\bar{B} \to \pi\ell^-\bar{\nu}_{\ell}$ decays with the light lepton and extracted $|V_{ub}|$ and the new WCs. Finally, using all these available data for the light and heavy leptons, we have given bounds on the couplings of the relevant SM effective field theory (SMEFT) operators and the probable NP scale $\Lambda$.
1.Precision studies of the post-CT18 LHC Drell-Yan data in the CTEQ-TEA global analysis
Authors:Ibrahim Sitiwaldi, Keping Xie, Alim Ablat, Sayipjamal Dulat, Tie-Jiun Hou, C. - P. Yuan
Abstract: In this study, we examine closely the impact of the post-CT18 LHC Drell-Yan data on parton distribution functions (PDFs) in the general CTEQ-TEA global analysis framework. We compare the two main theoretical predictions, the MCFM fixed order calculations at next-to-next-to-leading order (NNLO) and the ResBos2 NNLO matched to $q_T$ resummation up to next-to-next-to-next-to-leading logarithmic (N3LL) level. We find that the overall inclusive cross sections agree well but the fiducial distributions can differ at a percent level. We mainly discuss the result of the ResBos2 resummation calculation which yields a smaller Monte-Carlo uncertainty, and a better description to the post-CT18 LHC Drell-Yan data. We find that the majority of post-CT18 LHC Drell-Yan data are consistent with the ATLAS 7 TeV $W,Z$ data, which were included in the CT18A, but not CT18, fit and increases the strange quark distribution at the small $x$ region. The noticeable exception is that the ATLAS and LHCb 8 TeV $W$ data pull $d(\bar{d})$ quark PDFs to the opposite direction with respect to the ATLAS 7 TeV $W,Z$ data. The inclusion of these post-CT18 LHC Drell-Yan data sets in the CTEQ-TEA global analysis is to update the CT18 PDFs following similar trends as CT18Z PDFs. The parton luminosities and a few phenomenological implications with the fiducial $W^\pm,Z$ and inclusive $H,t\bar{t},t\bar{t}H$ productions at the 14 TeV LHC, as examples, are presented.
2.Analysis of $Ξ(1620)$ resonance and $\bar{K}Λ$ scattering length with chiral unitary approach
Authors:Takuma Nishibuchi, Tetsuo Hyodo
Abstract: We study the $\Xi(1620)$ resonance near the $\bar{K}\Lambda$ threshold in the light of the recent experimental constraints. The Belle collaboration have found a resonance peak of $\Xi(1620)$ slightly below the $\bar{K}^{0}\Lambda$ threshold in the $\pi^{+}\Xi^{-}$ invariant mass spectrum, and the ALICE collaboration have determined the $K^{-}\Lambda$ scattering length from the measurement of the momentum correlation functions in the heavy ion collisions. Using the effective range expansion, we classify the nature of the pole of the near-threshold eigenstate in terms of the scattering length, in the presence of the decay channel. It is shown that the quasibound state below the threshold can be described by only the scattering length, while the description of the resonance above the threshold requires the contribution from the effective range. Based on the chiral unitary approach, we construct a theoretical model which generates the pole of $\Xi(1620)$ below the $\bar{K}\Lambda$ threshold with relatively narrow width, as reported by the Belle collaboration. It is quantitatively demonstrated that the spectrum of the $\Xi(1620)$ quasibound state is distorted by the effect of the nearby $\bar{K}\Lambda$ threshold. We then construct another model which reproduces the $K^{-}\Lambda$ scattering length by the ALICE collaboration. In this case, the eigenstate pole does not appear in the physically relevant Riemann sheets, and the spectrum shows a cusp structure at the $\bar{K}\Lambda$ threshold. We finally examine the compatibility of the value of the $\bar{K}\Lambda$ scattering length and the subthreshold pole of $\Xi(1620)$ including the experimental uncertainties.
3.Bubble-assisted Leptogenesis
Authors:Eung Jin Chun, Tomasz P. Dutka, Tae Hyun Jung, Xander Nagels, Miguel Vanvlasselaer
Abstract: The typical mass scale of the lightest right-handed neutrino (RHN), in the thermal leptogenesis paradigm, is bounded from below at about $10^{11} \text{ GeV}$ due to a "strong washout" of the final asymmetry without a tuning of parameters. In this work, we explore the possibility of embedding thermal leptogenesis within a first-order phase transition (FOPT) such that RHNs remain massless until a FOPT arises. Their sudden and violent mass gain allows the neutrinos to become thermally decoupled, and the lepton asymmetry generated from their decay can be, in principle, free from the strong wash-out processes that conventional leptogenesis scenarios suffer from, albeit at the cost of new washout channels. We numerically quantify to what extent such a framework can alleviate strong-washout effects and we find the lower bound on the RHN mass, $M_N \sim 10^{7}\text{ GeV}$, below which bubble-assisted leptogenesis cannot provide an enhancement. We also study the signature possibly observable at GW terrestrial interferometers and conclude that bubble-assisted leptogenesis models with relatively light masses, $M_N \lesssim 5\times 10^9 \text{ GeV}$ may be probable.
4.A novel unbinned model-independent method to measure the CKM angle gamma in B+- --> DK+- decays with optimised precision
Authors:Jake Lane, Evelina Gersabeck, Jonas Rademacker
Abstract: We present a novel unbinned method to combine B+- --> DK+- and charm threshold data for the amplitude-model unbiased measurement of the CKM angle gamma in cases where the D meson decays to a three-body final state. The new unbinned approach avoids any kind of integration over the D Dalitz plot, to make optimal use the available information. We verify the method with simulated signal data where the D decays to KS pi+ pi-. Using realistic sample sizes, we find that the new method reaches the statistical precision on gamma of an unbinned model-dependent fit, i.e. as good as possible and better than the widely used model-independent binned approach, without suffering from biases induced by a mis-modeled D decay amplitude.
5.Probing Non-Standard Neutrino Interactions with Interference: Insights from Dark Matter and Neutrino Experiments
Authors:Jong-Chul Park, Gaurav Tomar
Abstract: Neutrino-electron scattering experiments play a crucial role in investigating the non-standard interactions of neutrinos. In certain models, these interactions can include interference terms that may affect measurements. Next-generation direct detection experiments, designed primarily for dark-matter searches, are also getting sensitive to probe the neutrino properties. We utilise the data from XENONnT, a direct detection experiment, and Borexino, a low-energy solar neutrino experiment, to investigate the impact of interference on non-standard interactions. Our study considers models with an additional $U(1)$, including $U(1)_{B-L}$, $U(1)_{L_e-L_\mu}$, and $U(1)_{L_e-L_\tau}$, to investigate the impact of interference on non-standard neutrino interactions. We demonstrate that this interference can lead to a transition between the considered non-standard interaction models in the energy range relevant to both the XENONnT and Borexino experiments. This transition can be used to distinguish among the considered models if any signals are observed at direct detection or neutrino experiments. Our findings underscore the importance of accounting for the interference and incorporating both direct detection and solar neutrino experiments to gain a better understanding of neutrino interactions and properties.
6.The warm inflation story
Authors:Arjun Berera
Abstract: Warm inflation has normalized two ideas in cosmology, that in the early universe the initial primordial density perturbations generally could be of classical rather than quantum origin and that during inflation, particle production from interactions amongst quantum field, and its backreaction effects, can occur concurrent with inflationary expansion. When we first introduced these ideas, both were met with resistance, but today they are widely accepted as possibilities with many models and applications based on them, which is an indication of the widespread influence of warm inflation. Open quantum field theory, which has been utilized in studies of warm inflation, is by now a relevant subject in cosmology, in part due to this early work. In this review I first discuss the basic warm inflation dynamics. I then outline how to compute warm inflation dynamics from first principles quantum field theory (QFT) and in particular how a dissipative term arises. Warm inflation models can have an inflaton mass bigger than the Hubble scale and the inflaton field excursion can remain sub-Planckian, thus overcoming the most prohibitive problems of inflation model building. I discuss the early period of my work in developing warm inflation that helped me arrive at these important features of its dynamics. Inflationary cosmology today is immersed in hypothetical models, which by now are acting as a diversion from reaching any endgame in this field. I discuss better ways to approach model selection and give necessary requirements for a well constrained and predictive inflation model. I point out a few warm inflation models that could be developed to this extent. I discuss how at this stage more progress would be made in this subject by taking a broader view on the possible early universe solutions that include not just inflation but the diverse range of options.
7.Higher-order corrections for $tqZ$ production
Authors:Nikolaos Kidonakis, Nodoka Yamanaka
Abstract: We present theoretical results for the associated production of a single top quark and a $Z$ boson ($tqZ$ production) at LHC energies. We calculate higher-order corrections from soft-gluon emission for this process. We compute the approximate NNLO (aNNLO) cross section at LHC energies, including uncertainties from scale dependence and from parton distributions. We also calculate the top-quark rapidity distribution. The aNNLO corrections are significant and enhance the NLO cross section, and their inclusion provides a more precise theoretical prediction.
8.Optimizing The Cut And Count Method In Phenomenological Studies
Authors:Baradhwaj Coleppa, Gokul B. Krishna, Agnivo Sarkar, Sujay Shil
Abstract: We introduce an optimization technique to discriminate signal and background in any phenomenological study based on the cut and count-based method. The core ideas behind this algorithm is the introduction of a ranking scheme that can quantitatively assess the relative importance of various observables involved in a new physics process, and a more methodical way of choosing what cuts to impose. The technique is an iterative process that works with the help of the MadAnalysis5 interface. Working in the context of a simple BSM scenario with a heavy Higgs boson that decays to four leptons via ZZ, we demonstrate how automating the cut and count process in this specific way results in an enhanced discovery potential compared with the more traditional way of imposing cuts.
9.Renormalization of the gluon distribution function in the background field formalism
Authors:Tolga Altinoluk, Guillaume Beuf, Jamal Jalilian-Marian
Abstract: We derive the Leading Order DGLAP evolution of gluon distribution function in the target light cone gauge starting from its standard operator definition. The derivation is performed using the background field formalism employed in the Color Glass Condensate effective theory of small $x$ QCD. We adopt Mandelstam-Leibbrandt prescription to regulate in an unambiguous way the spurious singularity appearing in the light-cone gauge Feynman propagator. UV divergences are regulated via conventional dimensional regularization. The methods introduced in this paper represent the first steps in the construction of a unified framework for QCD evolution, which could address collinear physics as well as small $x$ physics and gluon saturation.
10.Valence and sea parton correlations in double parton scattering from data
Authors:Edgar Huayra, Joao Vitor C. Lovato, Emmanuel G. de Oliveira
Abstract: The effective cross section of double parton scattering in proton collisions has been measured by many experiments with rather different results. Motivated by this fact, we assumed that the parton correlations in the transverse plane are different whether we have valence or sea partons. With this simple approach, we were able to fit the available data and found that sea parton pairs are more correlated in the transverse plane than valence--sea parton pairs.
11.Cogenesis of matter and dark matter from triplet fermion seesaw
Authors:Satyabrata Mahapatra, Partha Kumar Paul, Narendra Sahu, Prashant Shukla
Abstract: We propose a simple model in the type-III seesaw framework to explain the recently reported W-mass anomaly by CDF-II collaboration, neutrino mass, asymmetric dark matter, and baryon asymmetry of the Universe. We extend the standard model with a vector-like singlet lepton ($\chi$) and a hypercharge zero scalar triplet ($\Delta$) in addition to three hypercharge zero triplet fermions($\Sigma_i~,i=1,2,3$). A $Z_2$ symmetry is imposed under which $\chi$ and $\Delta$ are odd, while all other particles are even. As a result, the lightest $Z_2$ odd particle $\chi$ behaves as a candidate of dark matter. In the early Universe, the CP-violating out-of-equilibrium decay of heavy triplet fermions to the Standard Model lepton ($L$) and Higgs ($H$) generate a net lepton asymmetry, while that of triplet fermions to $\chi$ and $\Delta$ generate a net asymmetric dark matter. The lepton asymmetry is converted to the required baryon asymmetry of the Universe via the electroweak sphalerons, while the asymmetry in $\chi$ remains as a dark matter relic that we observe today. We introduce a singlet scalar $\phi$, with mass $m_\phi < m_\chi$, which not only assists to deplete the symmetric component of $\chi$ through the annihilation process: $\bar{\chi} \chi \to \phi \phi$ but also paves a path to detect dark matter $\chi$ at direct search experiments through $\phi-H$ mixing. The $Z_2$ symmetry is broken softly resulting in an unstable asymmetric dark matter with mass ranging from a few MeV to a few tens of GeV. The softly broken $Z_2$ symmetry also induces a vacuum expectation value (vev) of $\Delta$ due to which the asymmetry in $\Delta$ disappears. Moreover, the vev of $\Delta$ enhances the W-boson mass as reported by CDF-II collaboration with $7\sigma$ statistical significance, while keeping the $Z$-boson mass intact.
12.Cosmology with a supersymmetric local $B-L$ model
Authors:Kwang Sik Jeong, Wan-Il Park
Abstract: We propose a minimal gauged $U(1)_{B-L}$ extension of the minimal supersymmetric Standard Model (MSSM) which resolves the cosmological moduli problem via thermal inflation, and realizes late-time Affleck-Dine leptogensis so as to generate the right amount of baryon asymmetry at the end of thermal inflation. The present relic density of dark matter can be explained by sneutrinos, MSSM neutralinos, axinos, or axions. Cosmic strings from $U(1)_{B-L}$ breaking are very thick, and so the expected stochastic gravitational wave background from cosmic string loops has a spectrum different from the one in the conventional Abelian-Higgs model, as would be distinguishable at least at LISA and DECIGO. The characteristic spectrum is due to a flat potential, and may be regarded as a hint of supersymmetry. Combined with the resolution of moduli problem, the expected signal of gravitational waves constrains the $U(1)_{B-L}$ breaking scale to be $\mathcal{O}(10^{12-13})\,{\rm GeV}$. Interestingly, our model provides a natural possibility for explaining the observed ultra-high-energy cosmic rays thanks to the fact that the core width of strings in our scenario is very large, allowing a large enhancement of particle emissions from the cusps of string loops. Condensation of $LH_u$ flat-direction inside of string cores arises inevitably and can also be the main source of the ultra-high-energy cosmic rays accompanied by ultra-high-energy lightest supersymmetric particles.
1.Chemical potential of a hadronic fireball in the freeze-out stage
Authors:Yaroslav D. Krivenko-Emetov, Andriy I. Smetana
Abstract: This article explores the van der Waals gas model proposed to describe the hadronic stages of nuclear fireball evolution during the cooling stage. Two different models were proposed for the early and late stages of hadronization. At the initial stage, a two-component meson model consisting of $\pi^0$ and $\pi^+$ mesons was suggested, and at the later stage, a two-component nucleon model consisting of protons and neutrons was proposed. The interaction potential for both models was represented by a rectangular well, and the statistical sum was calculated using the saddle-point method. The analytic expressions for pressure and chemical potentials obtained from the model were compared with the corresponding numerical results of other authors obtained earlier using quantum chromodynamics (QCD) methods. The possibility of applying and using the effective chemical potential is also analyzed.
2.Gravitational Positivity for Phenomenologists: Dark Gauge Boson in the Swampland
Authors:Katsuki Aoki, Toshifumi Noumi, Ryo Saito, Sota Sato, Satoshi Shirai, Junsei Tokuda, Masahito Yamazaki
Abstract: The gravitational positivity bound gives quantitative ``swampland'' constraints on low-energy effective theories inside theories of quantum gravity. We give a comprehensive discussion of this bound for those interested in applications to phenomenological model building. We present a practical recipe for deriving the bound, and discuss subtleties relevant for realistic models. As an illustration, we study the positivity bound on the scattering of the massive gauge bosons in the Higgs/St\"{u}ckelberg mechanism. Under certain assumptions on gravitational amplitudes at high energy, we obtain a lower bound $m_{V} \gtrsim \Lambda_\mathrm{UV}^2 /g M_\mathrm{Pl}$ on the gauge boson mass $m_V$, where $g$ is the coupling constant of the gauge field, $M_\mathrm{Pl}$ is the reduced Planck mass and $\Lambda_\mathrm{UV}$ is the ultraviolet cutoff of the effective field theory. This bound can strongly constrain new physics models involving a massive gauge boson.
3.Magnetic dipole moments of $Ξ_{bc}$ and $Ω_{bc}$ baryons in light-cone QCD
Authors:U. Ozdem
Abstract: The magnetic dipole moments of the spin-$\frac{1}{2}$ bottom-charm baryons are extracted utilizing the QCD light-cone sum rule with the help of the photon distribution amplitudes. %When deriving magnetic dipole moments for these bottom-charm baryons, we have modeled them using two different interpolating currents. While deriving the magnetic dipole moments of the bottom charm baryons, two different possible interpolating currents that can be coupled to these states are taken into account. The magnetic dipole moments of the bottom-charm baryons include significant knowledge of their inner structure and geometric shape. The magnetic dipole moment results of the study are compared with estimations acquired in various other models and approaches.
4.Strange particle production in p+p collisions using \texttt{PYTHIA8} at LHC energy
Authors:Hushnud Hushnud, Kalyan Dey
Abstract: Strange particles being produced only during high-energy collisions carry important information regarding collision dynamics. Recent results of the ALICE Collaboration on strangeness enhancement in high-multiplicity p+p collisions have pointed out the importance of rope hadronization in high-energy nucleon-nucleon collisions. With the help of the \texttt{PYTHIA8} model, we made an attempt to discuss the strange particle production in high-energy p+p collisions at the LHC energy in the light of different color reconnection models and rope hadronization mechanism. The effect of color reconnection ranges on different observables is also discussed. The integrated yield of strange hadrons and bayon-to-meson ratios as a function charged particle multiplicity in p+p collisions at $\sqrt{s}$ = 13 TeV, is well described by the hadronization mechanism of color ropes together with QCD-based color reconnections scheme. The average transverse momentum, $\langle p_{\rm T}\rangle$, and its hardening as a function of $\langle dN/dy \rangle$ are explained by MPI-based color reconnection mechanism with a reconnection range, RR = 3.6, whereas it is underestimated by the rope hadronization model.
5.Physics implication from higher weak isospin decomposition
Authors:Phung Van Dong, Duong Van Loi
Abstract: The $SU(3)_L\otimes U(1)_X$ symmetry actually studied is directly broken to the electroweak symmetry $SU(2)_L\otimes U(1)_Y$ by a Higgs triplet, predicting a relevant new physics at TeV scale. This work argues, by contrast, that the higher weak isospin $SU(3)_L$ might be broken at a high energy scale, much beyond $1$ TeV, by a Higgs octet to an intermediate symmetry $SU(2)_L\otimes U(1)_{T_8}$ at TeV, before the latter $U(1)_{T_8}$ recombined with $U(1)_X$ defines (i.e., broken to) $U(1)_Y$ by a Higgs singlet. The new physics coupled to $SU(3)_L$ breaking phase is decoupled, whereas what remains is a novel family-nonuniversal abelian model, $U(1)_{T_8}\otimes U(1)_X$, significantly overhauling the standard model as well as yielding consistent results for neutrino mass, dark matter, $W$-mass anomaly, and FCNC, differently from the usual 3-3-1 model.
6.Medium modifications to jet angularities using SCET with Glauber gluons
Authors:Ankita Budhraja, Rishi Sharma, Balbeer Singh
Abstract: We perform a comprehensive analysis of medium modifications on ungroomed jet angularities, $\tau_a$, within the framework of Soft-Collinear Effective Theory with Glauber gluons (SCET$_{\rm G}$). Angularities are a one-parameter family of jet substructure observables with angularity exponent $a<2$ for infrared safety. Variation of the angularity exponent allows to modify the relative weighting of the collinear-to-soft radiations in the jet. In this article, we focus on angularity exponents $a<1$ and provide detailed results for $a=-1,0$, and $0.5$. Within SCET$_{\rm G}$, the interaction between jet and medium constituents is comprehended by off-shell Glauber gluons generated from the color gauge fields in the medium. While the medium modifications are incorporated in the jet function via the use of in-medium splitting functions, the soft function remains unmodified for $a<1$. For all values of $a$, we find that in the medium, the distributions are narrower and have a steeper fall compared to the vacuum ones. This redistribution of the ungroomed angularity spectrum is more apparent for a jet with a larger cone size. We also present results for the medium sensitivity towards $p_T$ of the jet and for a jet initiated in a less central event ($10-30\%$ centrality). Finally, we provide the ratios of nucleus-nucleus and proton-proton differential angularity distributions for different angularity exponents and for two values of the jet radius parameter.
7.Exploring dark matter models with global fits
Authors:Tomás E. Gonzalo
Abstract: In this conference paper I present the results from a few global studies of Dark Matter (DM) models, in light of recent constraints from direct detection, indirect detection and collider experiments. I show the most recent analysis of models of singlet Higgs-portal DM, where the DM particle is a scalar, vector, Majorana or Dirac fermion. I also present the results from a global study of an effective field theory of DM, where we find that the model shows a strong preference for a low scale of new physics. For all models I show the prospects for detection or exclusions with future experiments.
8.Mathematical Aspects of the Asymptotic Expansion in Contour Improved Perturbation Theory for Hadronic Tau Decays
Authors:Néstor G. Gracia, André H. Hoang, Vicent Mateu
Abstract: Recently, it was demonstrated that the discrepancy between the fixed-order (FOPT) and contour-improved (CIPT) perturbative expansions for $\tau$-lepton decay hadronic spectral function moments, which had been affecting the precision of $\alpha_s$ determinations for many years, is related to the CIPT expansion being inconsistent with the standard formulation of the operator product expansion (OPE). Even though the problem can be alleviated phenomenologically for the most part by employing a renormalon-free scheme for the gluon-condensate matrix element, the principal inconsistency of CIPT remains. The CIPT expansion is special because it is not a power expansion, but represents an asymptotic expansion in a sequence of functions of the strong coupling. In this article we provide a closer look at the mathematical aspects of the asymptotic sequence of the functions the CIPT method is based on, and we expose the origin of the CIPT inconsistency as well as the reasons for its apparent good convergence at low orders. Our results are of general interest, and may in particular provide a useful tool to check for the consistency of expansion methods that are similar to CIPT.
9.Effects of Kaluza-Klein Neutrinos on $R_{D}$ and $R_{D^{*}}$
Authors:Janus Capellan Aban, Chuan-Ren Chen, Chrisna Setyo Nugroho
Abstract: Recent measurements of $R_{D}$ and $R_{D^{*}}$ by the LHCb collaboration show deviations from their respective Standard Model values. These semileptonic $B$ meson decays, associated with $b\rightarrow c \tau \bar{\nu}$ transition, are pointing toward new physics beyond the Standard Model via leptonic flavor universality violation. In this paper, we show that such anomaly can be resolved by the cummulative Kaluza-Klein (KK) modes of singlet right-handed neutrino which propagates in the large extra dimensional space. We found that the number of extra dimension should be 2 to explain $R_{D}$ and $R_{D^{*}}$. We show that both $R_{D}$ and $R_{D^{*}}$ constraint the energy scale $M_{F}$ of this extra dimension which are compatible with the limits from lepton flavor violating tau decays. In contrast, our findings are in tension with the limits coming from the neutrino experiments which set the most stringent lower bound on $M_{F}$. The future measurements of $R_{D^{(*)}}^{exp}$ with reduced uncertainties will exclude this extra dimensional model with right-handed neutrino propagating in the bulk, if the central values stay.
10.Multimessenger Constraints on Radiatively Decaying Axions from GW170817
Authors:Melissa Diamond, Damiano F. G. Fiorillo, Gustavo Marques-Tavares, Irene Tamborra, Edoardo Vitagliano
Abstract: The metastable hypermassive neutron star produced in the coalescence of two neutron stars can copiously produce axions that radiatively decay into $\mathcal{O}(100)$~MeV photons. These photons can form a fireball with characteristic temperature smaller than $1\rm\, MeV$. By relying on X-ray observations of GW170817/GRB 170817A with CALET CGBM, Konus-Wind, and Insight-HXMT/HE, we present new bounds on the axion-photon coupling for axion masses in the range $1$-$400\,\rm MeV$. We exclude couplings down to $5\times 10^{-11}\,\rm GeV^{-1}$, complementing and surpassing existing constraints. Our approach can be extended to any feebly-interacting particle decaying into photons.
11.On the difference between Fixed-Order and Contour-Improved Perturbation Theory
Authors:Maarten Golterman SFSU, Kim Maltman York U. & CSSM, Adelaide U., Santiago Peris UAB, IFAE & SFSU
Abstract: Using standard mathematical methods for asymptotic series and the large-$\beta_0$ approximation, we define a Minimum Distance between the Fixed-Order perturbative series and the Contour-Improved perturbative series in the strong coupling $\alpha_s$ for finite-energy sum rules as applied to hadronic $\tau$ decays. This distance is similar, but not identical, to the Asymptotic Separation of Hoang and Regner, which is defined in terms of the difference of the two series after Borel resummation. Our results confirm a nonzero nonperturbative result in $\alpha_s$ for this Minimum Distance as a measure of the intrinsic difference between the two series, as well as a conflict with the Operator Product Expansion for Contour-Improved Perturbation Theory.
12.Looking forward to photon-coupled long-lived particles II: dark axion portal
Authors:Krzysztof Jodłowski
Abstract: The dark axion portal is a dimension-5 coupling between an axion-like particle (ALP), a photon, and a dark photon, which is one of the targets of the intensity frontier searches looking for $\sim\,$sub-GeV long-lived particles (LLPs). In this work, we re-examine the limits set by existing detectors such as CHARM and NuCal, and by future experiments such as FASER2, MATHUSLA, and SHiP. We extend previous works by i) considering several mass regimes of the Dark Sector (DS) particles, leading to an extended lifetime regime of the unstable species, ii) including LLPs production occurring in previously neglected vector meson decays that actually dominate the LLP yield, and iii) by implementing secondary LLP production. It takes place by Primakoff-like upscattering of lighter DS species into LLP on tungsten layers of neutrino emulsion detector FASER$\nu$2. This process will allow FASER2 to cover a significant portion of the $\gamma c\tau \sim 1\,m$ region of the parameter space that is otherwise difficult to cover due to the large ($\sim O(100)\,m$) distance between the primary LLP production point and the decay vessel, where LLP decays take place, which is required in typical beam-dumb experiments for SM background suppression.
1.Axion-like particle (ALP) portal freeze-in dark matter confronting ALP search experiments
Authors:Dilip Kumar Ghosh, Anish Ghoshal, Sk Jeesun
Abstract: The relic density of Dark Matter (DM) in the freeze-in scenario is highly dependent on the evolution history of the universe and changes significantly in a non-standard (NS) cosmological framework prior to Big Bang Nucleosynthesis (BBN). In this scenario, an additional species dominates the energy budget of the universe at early times (before BBN), resulting in a larger cosmological expansion rate at a given temperature compared to the standard radiation-dominated (RD) universe. To investigate the production of DM in the freeze-in scenario, we consider both standard RD and NS cosmological picture before BBN and perform a comparative analysis. We extend the Standard Model (SM) particle content with a SM singlet DM particle $\chi $ and an axion-like particle (ALP) $a$. The interactions between ALP, SM particles, and DM are generated by higher dimensional effective operators. This setup allows the production of DM $\chi$ from SM bath through the mediation of ALP, via ALP-portal processes. These interactions involve non-renormalizable operators, leading to ultraviolet (UV) freeze-in, which depends on the reheating temperature ($T_{RH}$) of the early universe. In the NS cosmological scenario, the faster expansion rate suppresses the DM production processes, allowing for enhanced effective couplings between the visible and dark sectors to satisfy the observed DM abundance compared to RD scenario. This improved coupling increases the detection prospects for freeze-in DM via the ALP-portal, which is otherwise challenging to detect in RD universe due to small couplings involved. Using an effective field theory set-up, we show that various ALP searches such as in FASER, DUNE, and SHiP, etc. will be able to probe significant parameter space depending on the different model parameters.
2.Compatibility of CE$ν$NS with muon $g-2$, $W$ mass, and $R(D^{(*)})$ in a gauged ${L_μ-L_τ}$ with a scalar LQ
Authors:Chuan-Hung Chen, Cheng-Wei Chiang, Chun-Wei Su
Abstract: Coherent elastic neutrino-nucleon scattering, challenged by the low nucleus recoil energy of a few tens of keV, has been observed by the COHERENT experiment using targets CsI and Ar. We study the contribution of a light $Z'$ mediator in a gauged $U(1)_{L_\mu-L_\tau}$ symmetry. In contrast to the mechanism from the kinetic mixing between $U(1)_{\rm em}$ and $U(1)_{L_\mu-L_\tau}$, we adopt a dynamical symmetry breaking of the $U(1)_{L_\mu-L_\tau}$ by employing an extra Higgs doublet. As a result, the weak charge mediated by $Z'$ only depends on the mass of light gauge boson. Since two Goldstone bosons are required to serve as the longitudinal components of $Z$ and $Z'$, the model does not contain a physical CP-odd scalar. Using the introduced Higgs doublet carrying the $U(1)_{\mu-\tau}$ charge, new Higgs decay channels $h\to Z_1 Z_1/Z_1 Z_2$ with percent-level branching fractions become accessible. The $W$-mass anomaly observed by CDF II can be resolved by enhancing the oblique parameter $T$. With the flavored gauge symmetry, the Yukawa couplings to fermion flavors are strictly limited. By utilizing the characteristic and introducing a scalar leptoquark $S^{\frac{1}{3}}=(3,1,2/3)$ that uniquely couples to the $\tau$ lepton, the excesses of $R(D)$ and $R(D^*)$ can be explained. Moreover, $\tau \to \mu (Z_1\to ) e^- e^+$ via the resonant light gauge boson decay can reach the sensitivity of Belle II at an integrated luminosity of 50 ab$^{-1}$.
3.A minimal inverse seesaw model with $S_4$ flavour symmetry
Authors:Bikash Thapa, Sunita Barman, Sompriti Bora, Ng. K. Francis
Abstract: We construct an $S_4$ flavour symmetric minimal inverse seesaw model where the standard model is extended by adding two right-handed and two standard model gauge singlets neutrinos to explain the origin of tiny neutrino masses. The resulting model describes the lepton mass spectra and flavour mixing quite well for the case of the normal hierarchy of neutrino masses. The prediction of the model on the Dirac CP-violating phase is centered around $370.087^\circ$. Furthermore, using the allowed region for the model parameters, we have calculated the value of the effective Majorana neutrino mass, $\lvert\langle m_{ee}\rangle\rvert$, which characterizes neutrinoless double beta decay.
4.Soliton Solutions and Conservation Laws for a Self-interacting Scalar Field in \(φ^{4}\) Theory
Authors:Muhammad Al-Zafar Khan, Mervlyn Moodley, Francesco Petruccione
Abstract: We calculate soliton solutions to the scalar field equation of motion that arises for the 4th-order extended Lagrangian (\(\phi^{4}\) theory) in quantum field theory using the extended hyperbolic tangent and the sine-cosine methods. Using the former technique, ten complex soliton waves are obtained; we graphically represent three of these profiles using density plots. In the latter case, two real soliton solutions are obtained, of which, we demonstrate the wave profile for the positive case. Using the multiplier method, we calculate conservation laws in \((1 + 1)\)-, \((2 + 1)\)-, and \((3 + 1)\)-dimensions producing three, six, and ten conservation laws respectively. Lastly, we reflect on the application of conservation laws in particle physics and phenomenology.
5.Decays $τ\to 3K ν_τ$ in $U(3)\times U(3)$ quark NJL model
Authors:M. K. Volkov, A. A. Pivovarov, K. Nurlan
Abstract: The widths of the decays $\tau \to K^- K^+ K^- \nu_\tau$ and $\tau \to K^- K^0 \bar{K}^0 \nu_\tau$ are calculated in the $U(3)\times U(3)$ chiral quark NJL model. Four channels are considered: contact, axial vector, vector and pseudoscalar channels. It is shown that the dominant contribution is given by the axial vector channel with an intermediate $\phi$ meson. The obtained results are in satisfactory agreement with the experimental data.
6.Chiral and trace anomalies in Deeply Virtual Compton Scattering II: QCD factorization and beyond
Authors:Shohini Bhattacharya, Yoshitaka Hatta, Werner Vogelsang
Abstract: We extend the discussion of the recently discovered 'anomaly poles' in QCD Compton scattering. We perform the complete one-loop calculation of the Compton amplitude using momentum transfer $t$ as the regulator of collinear divergences. In the gluon channel, we confirm the presence of poles $1/t$ in both the real and imaginary parts of the amplitude. In the quark channel, we find unexpected infrared single $1/\epsilon$ and double $1/\epsilon^2$ poles. We then perform the one-loop calculation of the leading-twist quark generalized parton distributions (GPDs) with the same regulators and find that all these singular terms can be systematically absorbed into the GPDs, showing that QCD factorization is restored to this order. Having established this, we discuss the fate of the $1/t$ poles. We argue that they become the nonperturbative building blocks of GPDs that encode the chiral and trace anomalies of QCD, in a way consistent with the known constraints these anomalies impose on the nucleon axial and gravitational form factors. The scope of research on GPDs can therefore be expanded to address the manifestation and implications of quantum anomalies in high-energy exclusive processes.
7.Searching for the open flavor tetraquark $T^{++}_{c\bar{s}0}(2900)$ in the process $B^+\to K^+ D^+ D^-$
Authors:Man-Yu Duan, En Wang, Dian-Yong Chen
Abstract: Inspired by recent observations of $T_{c\bar{s}0}(2900)^0$ in the $D_s^+ \pi^-$ invariant mass distribution of $B^0 \to \bar{D}^0 D_s^+ \pi^-$ decay and $T_{c\bar{s}0}(2900)^{++}$ in the $D_s^+ \pi^+$ invariant mass distribution of $B^+ \to D^- D_s^+ \pi^+$ decay, we investigate the $T_{c\bar{s}0}(2900)^{++}$ contribution to the $B^+ \to K^+ D^+ D^-$ decay in a molecular scenario, where we consider $T_{c\bar{s}0}(2900)r^{++}$ as a $D^{\ast +} K^{\ast+}$ molecular state. Our estimations indicate that the fit fraction of $T_{c\bar{s}0}(2900)^{++}$ in the $B^+ \to K^+ D^+ D^-$ is about $12.5\%$, and its signal is visible in the $D^+ K^+$ invariant mass distribution. With the involvement of $T_{c\bar{s}0}(2900)^{++}$, the fit fractions of $\chi_{c0}(3915)$ and $\chi_{c2}(3930)$ may be much different with the ones obtained by the present amplitude analysis [Phys. Rev. D \textbf{102}, 112003 (2020)], which may shed light on the long standing puzzle of $\chi_{c0}(3915)$ as the conventional charmonium.
8.UV-IR interplay in axion flavour violation
Authors:Luca Di Luzio, Alfredo Walter Mario Guerrera, Xavier Ponce Díaz, Stefano Rigolin
Abstract: Flavour-violating axions appear in models where the Peccei-Quinn(PQ) charges are generation non-universal. Consequently, this charge arrangement will also generate flavour violation in the UV sector. The typical way of implementing such an axion in a UV completion is with a DFSZ model, containing 2 Higgs doublets. In this talk we will present how to parameterize the flavour violation in the UV such that we can find a direct correlation with the flavour violation of the axion. Finally, we show in an example how this connection can help in giving information about the UV completion if an axion is found in a flavour-violating channel.
9.Absence of inhomogeneous chiral phases in 2+1-dimensional four-fermion and Yukawa models
Authors:Laurin Pannullo, Marc Winstel
Abstract: We show the absence of an instability of homogeneous (chiral) condensates against spatially inhomogeneous perturbations for various 2+1-dimensional four-fermion and Yukawa models. All models are studied at non-zero baryon chemical potential, while some of them are also subjected to chiral and isospin chemical potential. The considered theories contain up to 16 Lorentz-(pseudo)scalar fermionic interaction channels. We prove the stability of homogeneous condensates by analyzing the bosonic two-point function, which can be expressed in a purely analytical form at zero temperature. Our analysis is presented in a general manner for all of the different discussed models. We argue that the absence of an inhomogeneous chiral phase (where the chiral condensate is spatially non-uniform) follows from this lack of instability. Furthermore, the existence of a moat regime, where the bosonic wave function renormalization is negative, in these models is ruled out.
10.A nearly Dirichlet Higgs for lower-scale warped extra dimensions
Authors:Mariana Frank, Nima Pourtolami, Manuel Toharia
Abstract: We consider a minimal extension of the Standard Model in warped extra dimensions, with fields propagating in the bulk including a bulk SM-like Higgs doublet. We show that the Higgs can acquire a non-trivial oscillatory VEV, strongly localized towards the TeV brane, but such that its value at that brane could be highly suppressed due to its oscillatory behaviour. Within the minimal Randall-Sundrum metric background, this oscillatory VEV can alleviate the bounds coming from oblique precision electroweak parameters, such that the KK gluon mass can be around 3 TeV (instead of about 8 TeV for the usual non-oscillatory bulk Higgs). We also discuss the stability of the configuration as well as the naturalness of the model parameters.
11.Electroweak radiative corrections to polarized top quark pair production
Authors:A. Arbuzov a, S. Bondarenko a, L. Kalinovskaya b, R. Sadykov b, V. Yermolchyk b, c
Abstract: Electroweak effects in the $e^+e^- \to t \bar{t}$ annihilation process are described with taking into account polarization of the initial and final particles. We investigate the effects of complete one-loop electroweak radiative corrections and higher-order radiative effects to the total cross section and analyze different types of asymmetries for polarized initial and final states for typical energies and degrees of polarization of the ILC and CLIC projects. Numerical results are obtained with the help of Monte Carlo tools: the ReneSANCe event generator and the MCSANC integrator.
1.Novel model for particle emission in small collision systems
Authors:Dimitar Mihaylov, Jaime González González
Abstract: Collider experiments provide an opportunity to produce particles at close distances and momenta. The measured correlation functions between particles can provide information on both the effective emission source and the interaction potential. In recent years, experiments at the LHC have shown that precision studies of the strong interaction are possible using correlation techniques, provided a good handle on the source function. The current work presents a new numerical framework called Common Emission in CATS (CECA), capable of simulating the effective emission source of an N-body system based on the properties of the single particles. The framework differentiates between primordial particle emission and particle production through resonances, allowing to verify the hypothesis proposed by the ALICE collaboration that a common baryon-baryon emission source is present in small collision systems. The new framework is used to analyze ALICE data on pp and p$\Lambda$ correlations and compare the results to previous studies based on the common emission source scenario. It is demonstrated that the best fit to the p$\Lambda$ correlation data is obtained using a scattering length of $1.15\pm0.07$ fm in the S=1 channel.
2.QCD mesonic screening masses using Gribov quantization
Authors:Sumit, Najmul Haque, Binoy Krishna Patra
Abstract: The screening masses of mesons provide a gauge invariant and definite order parameter of chiral symmetry restoration. Different mesonic correlation lengths for flavor non-singlets, at least up to NLO, are well-defined gauge invariant physical quantities calculated earlier using the perturbative resummation techniques. The NLO perturbative results match the available non-perturbative lattice QCD results at the high-temperature regime. We have studied the spatial correlation lengths of various mesonic observables using the non-perturbative Gribov resummation, both for quenched QCD and (2 + 1) flavor QCD. The study follows the analogies with the NRQCD effective theory, a well-known theory for studying heavy quarkonia at zero temperature.
3.Geometrical causality: casting Feynman integrals into quantum algorithms
Authors:German F. R. Sborlini
Abstract: The calculation of higher-order corrections in Quantum Field Theories is a challenging task. In particular, dealing with multiloop and multileg Feynman amplitudes leads to severe bottlenecks and a very fast scaling of the computational resources required to perform the calculation. With the purpose of overcoming these limitations, we discuss efficient strategies based on the Loop-Tree Duality, its manifestly causal representation and the underlying geometrical interpretation. In concrete, we exploit the geometrical causal selection rules to define a Hamiltonian whose ground-state is directly related to the terms contributing to the causal representation. In this way, the problem can be translated into a minimization one and implemented in a quantum computer to search for a potential speed-up.
4.Testing Bell inequalities and entanglement with di-boson final states
Authors:Luca Marzola
Abstract: We explore the phenomenology of quantum entanglement at collider experiments by computing the polarization density matrix of processes yielding two massive gauge bosons. After reviewing the formalism, we detail observables suitable to test the presence of entanglement and quantum correlations in the di-boson system. The implied violation of Bell inequalities can be observed with future data at the LHC in the decays of the Higgs boson to $Z$ boson pairs.
5.Exploring Models with Modular Symmetry in Neutrino Oscillation Experiments
Authors:Priya Mishra, Mitesh Kumar Behera, Papia Panda, Monojit Ghosh, Rukmani Mohanta
Abstract: Our study aims to investigate the viability of neutrino mass models that arise from discrete non-Abelian modular symmetry groups, i.e., $\Gamma_N$ with ($N=1,2,3,\dots$) in the future neutrino experiments T2HK, DUNE, and JUNO. Modular symmetry reduces the usage of flavon fields compared to the conventional discrete flavor symmetry models. Theories based on modular symmetries predict the values of leptonic mixing parameters, and therefore, these models can be tested in future neutrino experiments. In this study, we consider three models based on the $A_4$ modular symmetry, i.e., Model-A, B, and C such a way that they predict different values of the oscillation parameters but still allowed with respect to the current data. In the future, it is expected that T2HK, DUNE, and JUNO will measure the neutrino oscillation parameters very precisely, and therefore, some of these models can be excluded in the future by these experiments. We have estimated the prediction of these models numerically and then used them as input to scrutinize these models in the neutrino experiments. Assuming the future best-fit values of $\theta_{23}$ and $\delta_{\rm CP}$ remain the same as the current one, our results show that at $5 \sigma$ C.L, Model-A can be excluded by T2HK whereas Model-B can be excluded by both T2HK and DUNE. Model-C cannot be excluded by T2HK and DUNE at $5 \sigma$ C.L. Further; our results show that JUNO alone can exclude Model-B at an extremely high confidence level if the future best-fit of $\theta_{12}$ remains at the current-one. We have also identified the region in the $\theta_{23}$ - $\delta_{\rm CP}$ parameter space, for which Model-A cannot be separated from Model-B in T2HK and DUNE.
6.Two-Real-Singlet Model Benchmark Planes -- A Moriond Update
Authors:Tania Robens
Abstract: I present an update on the the Benchmark Planes in the Two-Real-Singlet Model (TRSM), a model that enhances the Standard Model (SM) scalar sector by two real singlets, where an additional Z2 x Z2' symmetry is imposed. I discuss the case where all fields acquire a vacuum expectation value, such that the model contains in total 3 CP-even neutral scalars that can interact with each other. I remind the readers of the previously proposed benchmark planes, current constraints, and possible signatures at current and future colliders. This is an update for Moriond 2023 of results presented in arXiv:2209.10996.
7.Short Baseline Oscillations and the Gallium Mystery
Authors:Vedran Brdar
Abstract: Data from several neutrino experiments suggest an anomalous neutrino flavor transition across relatively short baselines which is in conflict with the three-flavor neutrino oscillation paradigm. In particular, MiniBooNE and BEST collaborations have reported anomalous findings at $\sim 5\sigma$. In this contribution, such measurements and their possible explanations within and beyond the Standard Model are discussed.
8.Next-to-leading-logarithmic PanScales showers for Deep Inelastic Scattering and Vector Boson Fusion
Authors:Melissa van Beekveld, Silvia Ferrario Ravasio
Abstract: We introduce the first family of parton showers that achieve next-to-leading logarithmic (NLL) accuracy for processes involving a $t$-channel exchange of a colour-singlet, and embed them in the PanScales framework. These showers are applicable to processes such as deep inelastic scattering (DIS), vector boson fusion (VBF), and vector boson scattering (VBS). We extensively test and verify the NLL accuracy of the new showers at both fixed order and all orders across a wide range of observables. We also introduce a generalisation of the Cambridge-Aachen jet algorithm and formulate new DIS observables that exhibit a simple resummation structure. The NLL showers are compared to a standard transverse-momentum ordered dipole shower, serving as a proxy for the current state-of-the-art leading-logarithmic showers available in public codes. Depending on the observable, we find discrepancies at NLL of the order of $15\%$. We also present some exploratory phenomenological results for Higgs production in VBF. This work enables, for the first time, to resum simultaneously global and non-global observables for the VBF process at NLL accuracy.
9.Precision prediction at the LHC of a democratic up-family philic KSVZ axion model
Authors:Anupam Ghosh, Partha Konar
Abstract: In this work, we study the $SU(2)_L$ singlet complex scalar extended KSVZ model that, in addition to providing a natural solution to the strong-CP problem by including a global Peccei-Quinn symmetry, also furnishes two components of dark matter that satisfy observer relic density without fine-tuning of model parameters. Furthermore, this model provides a rich phenomenology by introducing a vector-like quark whose presence can be sensed in collider experiments and dark matter production mechanisms. We explore the possibility of democratic Yukawa interaction of the vector-like quark with all up-type quarks and scalar dark matter candidate. We also employ next-to-leading order NLO-QCD correction for VLQ pair production to study a unique search at the LHC, generating a pair of boosted tops with sizeable missing transverse momentum. Multivariate analysis with jet substructure variables has a strong ability to explore a significant parameter space of this model at the 14 TeV LHC.
10.NeatIBP 1.0, A package generating small-size integration-by-parts relations for Feynman integrals
Authors:Zihao Wu, Janko Boehm, Rourou Ma, Hefeng Xu, Yang Zhang
Abstract: In this work, we present the package {\sc NeatIBP}, which automatically generates small-size integration-by-parts (IBP) identities for Feynman integrals. Based on the syzygy and module intersection techniques, the generated IBP identities' propagator degree is controlled and thus the size of the system of IBP identities is shorter than that generated by the standard Laporta algorithm. This package is powered by the computer algebra systems {\sc Mathematica} and {\sc Singular}, and the library {\sc SpaSM}. It is parallelized on the level of Feynman integral sectors. The generated small-size IBP identities can subsequently be used for either finite field reduction or analytic reduction. We demonstrate the capabilities of this package on several multi-loop IBP examples.
11.The QED of Bernabéu-Tarrach sumrule for electric polarizability and its implication for the Lamb shift
Authors:Volodymyr Biloshytskyi, Iulian Ciobotaru-Hriscu, Franziska Hagelstein, Vadim Lensky, Vladimir Pascalutsa
Abstract: We attempt to rehabilitate a sumrule (proposed long ago by Bernab\'eu and Tarrach) which relates the electric polarizability of a particle to the total photoabsorption of quasi-real longitudinally polarized photons by that particle. We discuss its perturbative verification in QED, which is largely responsible for the scepticism about its validity. The failure of the QED test can be understood via the Sugawara-Kanazawa theorem and is due to the non-vanishing contour contribution in the pertinent dispersion relation. We show another example where this contribution is absent and the perturbative test works exactly. On the empirical side, we show that the sumrule gives a reasonable estimate of the $\pi N$-channel contribution to the proton electric polarizability. If this sumrule is valid indeed, there should be a sumrule for the so-called ``subtraction function'' entering the data-driven calculations of the polarizability effects in the Lamb shift. We have written down a possible sumrule for the subtraction function and verified it in a perturbative calculation.
1.Impact of errors in the magnetic field measurement on the precision determination of neutrino oscillation parameters at the proposed ICAL detector at INO
Authors:Honey Khindri, D. Indumathi, Lakshmi S. Mohan
Abstract: The magnetised iron calorimeter (ICAL) detector proposed at the India-based Neutrino Observatory will be a 51 kton detector made up of 151 layers of 56 mm thick soft iron with 40 mm air gap in between where the RPCs, the active detectors, will be placed. The main goal of ICAL is to make precision measurements of the neutrino oscillation parameters using the atmospheric neutrinos as source. The charged current interactions of the atmospheric muon neutrinos and anti-neutrinos in the detector produce charged muons. The magnetic field, with a maximum value of $\sim$ 1.5 T in the central region of ICAL, is a critical component since it will be used to distinguish the charges and determine the momentum and direction of these muons. It is difficult to measure the magnetic field inside the iron. The existing methods can only estimate the internal field and hence will be prone to error. This paper presents the first simulations study of the effect of errors in the measurement of the magnetic field in ICAL on its physics potential, especially the neutrino mass ordering and precision measurement of oscillation parameters in the 2--3 sector. The study is a GEANT4-based analysis, using measurements of the magnetic field at the prototype ICAL detector. We find that there is only a small effect on the determination of the mass ordering. While local fluctuations in the magnetic field measurement are well-tolerated, calibration errors must remain well within 5\% to retain good precision determination of the parameters $\sin^2\theta_{23}$ and $\Delta m^2_{32}$.
2.Experimental signatures of subtleties in the Brout-Englert-Higgs mechanism
Authors:Axel Maas
Abstract: Subtle, but long-known, field-theoretical aspects require a more refined treatment of gauge theories involving a Brout-Englert-Higgs effect. This refinement can be done analytically using the Fr\"ohlich-Morchio-Strocchi mechanism. In the standard model, this leads to slight, but in principle detectable, quantitative changes in observables. This can have significant implications for current and future colliders, which are investigated for a few sample processes.
3.Extraction of unpolarized transverse momentum distributions from fit of Drell-Yan data at N$^4$LL
Authors:Valentin Moos, Ignazio Scimemi, Alexey Vladimirov, Pia Zurita
Abstract: We present an extraction of unpolarized transverse momentum dependent parton distributions functions and Collins-Soper kernel from the fit of Drell-Yan and weak-vector boson production data. The analysis is done at the N$^4$LL order of perturbative accuracy, using a flavor dependent non-perturbative ansatz. The estimation of uncertainties is done with the replica method and, for the first time, includes the propagation of uncertainties due to the collinear distributions.
4.Axion like particles, fifth force and neutron interferometry
Authors:Antonio Capolupo, Salvatore Marco Giampaolo, Aniello Quaranta
Abstract: We report on recent result according to which the fermion-fermion interaction mediated by axions and axion-like particles can be revealed by means of neutron interferometry. We assume that the initial neutron beam is split in two beams which are affected by differently oriented magnetic fields, in order that the phase difference depends only by the axion-induced interaction. In this way, the phase difference is directly related to the presence of axions.
1.Vacuum stability and Q-ball formation in the Type II Seesaw model
Authors:Naoyuki Haba, Yasuhiro Shimizu, Toshifumi Yamada
Abstract: We investigate vacuum stability and Q-ball formation in the Type II seesaw model by considering the effective potential for scalar fields, taking into account renormalization effects. We find that the quartic coupling for the triplet Higgs can vanish at a high energy scale, creating a flat direction where Q-ball formation can occur. If Q-balls are produced, they eventually decay into leptons via neutrino Yukawa couplings with the triplet Higgs. If this decay occurs above the electroweak scale, the leptogenesis scenario can work, and the baryon number is produced via the sphaleron effect. We show that there are parameter regions where the above scenario occurs, taking into account phenomenological constraints.
2.Parameter space for testable leptogenesis
Authors:Yannis Georis
Abstract: Extending the Standard Model with right-handed neutrinos provides a minimal explanation for both light neutrino masses (through the type-I seesaw mechanism) and the baryon asymmetry of our universe (through leptogenesis). We map here for the first time the range of heavy neutrino mixing angle consistent with both neutrino masses and leptogenesis in a scenario with 3 generations of right-handed neutrinos with Majorana masses between 50 MeV and 70 TeV. Due to the presence of a third degree of freedom that remains much more feebly coupled to the Standard Model thermal bath, we observe that the parameter space is much larger compared to the minimal scenario with 2 generations. This greatly enhances the testability prospects for low-scale leptogenesis and, in the most optimistic scenario, would allow experimentalists not only to discover right-handed neutrinos but also to perform consistency checks of the model.
3.Elastic proton-neutron and antiproton-neutron scattering in holographic QCD
Authors:Akira Watanabe, Sayed Anwar Sirat, Zhibo Liu
Abstract: The total and differential cross sections of the elastic proton-neutron and antiproton-neutron scattering are studied in a holographic QCD model, focusing on the Regge regime. Taking into account the Pomeron and Reggeon exchange, which are described by the Reggeized spin-2 glueball and vector meson propagator respectively, those cross sections are obtained. It is presented that the currently available experimental data of the total cross sections can be well described within the model. Once a single adjustable parameter is determined with the total cross section data, the differential cross sections can be calculated without any additional parameters. Although the available differential cross section data are limited, it is found that our predictions are consistent with those.
4.Baryon masses estimate in heavy flavor QCD
Authors:María Gómez-Rocha, Jai More, Kamil Serafin
Abstract: We apply the renormalization group procedure for effective particles (RGPEP) to the QCD eigenvalue problem for only heavy quarks. We derive the effective Hamiltonian that acts on the Fock space by solving the RGPEP equation up to second order in powers of the coupling constant. The eigenstates that contain three quarks and two or more gluons are eliminated by inserting a gluon-mass term in the component with one gluon and formulate the eigenvalue problem for baryons. We estimate masses for $bbb$ and $ccc$ states and find that the results match the estimates obtained in lattice QCD and in quark models.
5.The Standard Model Effective Field Theory up to Mass Dimension 12
Authors:R. V. Harlander, T. Kempkens, M. C. Schaaf
Abstract: We present a complete and non-redundant basis of effective operators for the Standard Model Effective Field Theory up to mass dimension 12 with three generations of fermions. We also include operators coupling to gravity via the Weyl tensor up to mass dimension 11. The results are obtained by implementing the algorithm of Li et al., and provided in the form of ancillary files.
6.Probing compressed mass spectra in the type-II seesaw model at the LHC
Authors:Saiyad Ashanujjaman, Siddharth P. Maharathy
Abstract: Despite a great deal of effort in searching for the triplet-like Higgses in the type-II seesaw model, evidence for their production is yet to be found at the LHC. As such, one might be in the balance regarding this model's relevance at the electroweak scale. In this work, we peruse a scenario, akin to compressed mass spectra in Supersymmetry, which might have eluded the experimental searches thus far. We perform a multivariate analysis to distinguish signals with a pair of same-sign leptons with low invariant mass from the SM processes, including those accruing from fake leptons and electron charge misidentification, and find that a significant part of the hitherto unconstrained parameter space could be probed with the already collected Run 2 13 TeV LHC and future HL-LHC data.
7.Updated analysis of near-threshold heavy quarkonium production for probe of proton's gluonic gravitational form factors
Authors:Yuxun Guo, Xiangdong Ji, Yizhuang Liu, Jinghong Yang
Abstract: There has been growing interest in the near-threshold production of heavy quarkonium which can access the gluonic structure in the nucleon. Previously we studied this process with quantum chromodynamics (QCD) and showed that it can be factorized with the gluon generalized parton distributions (GPDs) in the heavy quark limit. We further argued that the hadronic matrix element is dominated by its leading moments corresponding to the gluonic gravitational form factors (GFFs) in this limit. Since then, there have been many new developments on this subject. More experimental measurements have been made and published, and the lattice simulation of gluonic GFFs has been improved as well. In this work, we make an important revision to a previous result and perform an updated analysis with the new inputs. We also study the importance of the large momentum transfer to extract these gluonic structures reliably in this framework.
1.Neutrino oscillations induced by chiral torsion
Authors:Riya Barick, Indrajit Ghose, Amitabha Lahiri
Abstract: Neutrino mixing is caused by the fact that neutrino flavors are not eigenstates of the free Hamiltonian. This causes oscillations among different neutrino flavors. When neutrinos pass through a medium, weak interactions produce different effective masses for neutrinos of different flavors, leading to a modification of the mixing parameters. In curved spacetime there is an additional contribution to neutrino Hamiltonian from a torsion-induced four-fermion interaction, which also causes neutrino mixing while propagating through fermionic matter. We provide an outline of the calculation of this effect on neutrino oscillation.
2.Effect of spatially oscillating field on Schwinger pair production
Authors:Orkash Amat, Li-Na Hu, Mamat Ali Bake, Melike Mohamedsedik, B. S. Xie
Abstract: Effect of spatially oscillating fields on the electron-positron pair production is studied numerically and analytically when the work done by the electric field over its spatial extent is smaller than twice the electron mass. Under large spatial scale, we further explain the characteristics of the position and momentum distribution via tunneling time, tunneling distance and energy gap between the positive and negative energy bands in the Dirac vacuum. Our results show that the maximum reduced particle number is about five times by comparing to maximum number for non-oscillating field. Moreover, the pair production results via Dirac-Heisenberg-Wigner formalism can be also calculated by using local density approximation and analytical approximation method when spatial oscillating cycle number is large. Moreover, in case of large spatial scale field, the position distribution of created particles could be interpreted by the tunneling time.
3.Kaon Decays beyond the Standard Model
Authors:Stefan Schacht
Abstract: We review a new method in order to determine the parameter $\bar{\eta}$ of the Cabibbo-Kobayashi-Maskawa matrix from $K\rightarrow \mu^+\mu^-$ decays, using interference effects in the time-dependent decay rate. Furthermore, we discuss a new precision relation for the phase-shift of the time-dependent oscillation. The new methodology enables the discovery potential of future time-dependent measurements of $K\rightarrow \mu^+\mu^-$ decays for physics beyond the Standard Model.
4.Dispersive Analysis of $B\to K^{(*)}$ and $B_s\to φ$ Form Factors
Authors:Nico Gubernari, Méril Reboud, Danny van Dyk, Javier Virto
Abstract: We propose a stronger formulation of the dispersive (or unitarity) bounds \`a la Boyd-Grinstein-Lebed (BGL), which are commonly applied in analyses of the hadronic form factors for $B$ decays. In our approach, the existing bounds are split into several new bounds, thereby disentangling form factors that are jointly bounded in the common approach. This leads to stronger constraints for these objects, to a significant simplification of our numerical analysis, and to the removal of spurious correlations among the form factors. We apply these novel bounds to $\bar{B}\to \bar{K}^{(*)}$ and $\bar{B}_s\to \phi$ form factors by fitting them to purely theoretical constraints. Using a suitable parametrization, we take into account the form factors' below-threshold branch cuts arising from on-shell $\bar{B}_s \pi^0$ and $\bar{B}_s \pi^0 \pi^0$ states, which so-far have been ignored in the literature. In this way, we eliminate a source of hard-to-quantify systematic uncertainties. We provide machine readable files to obtain the full set of the $\bar{B}\to \bar{K}^{(*)}$ and $\bar{B}_s\to \phi$ form factors in and beyond the entire semileptonic phase space.
1.Flavor-dependent long-range neutrino interactions in DUNE & T2HK: alone they constrain, together they discover
Authors:Masoom Singh, Mauricio Bustamante, Sanjib Kumar Agarwalla
Abstract: Discovering new neutrino interactions would represent evidence of physics beyond the Standard Model. We focus on new flavor-dependent long-range neutrino interactions mediated by ultra-light mediators, with masses below $10^{-10}$ eV, introduced by new lepton-number gauge symmetries $L_e-L_\mu$, $L_e-L_\tau$, and $L_\mu-L_\tau$. Because the interaction range is ultra-long, nearby and distant matter - primarily electrons and neutrons - in the Earth, Moon, Sun, Milky Way, and the local Universe, may source a large matter potential that modifies neutrino oscillation probabilities. The upcoming Deep Underground Neutrino Experiment (DUNE) and the Tokai-to-Hyper-Kamiokande (T2HK) long-baseline neutrino experiments will provide an opportunity to search for these interactions, thanks to their high event rates and well-characterized neutrino beams. We forecast their probing power. Our results reveal novel perspectives. Alone, DUNE and T2HK may strongly constrain long-range interactions, setting new limits on their coupling strength for mediators lighter than $10^{-18}$ eV. However, if the new interactions are subdominant, then both DUNE and T2HK, together, will be needed to discover them, since their combination lifts parameter degeneracies that weaken their individual sensitivity. DUNE and T2HK, especially when combined, provide a valuable opportunity to explore physics beyond the Standard Model.
2.Symmetries for the 4HDM: extensions of cyclic groups
Authors:Jiazhen Shao, Igor P. Ivanov
Abstract: Multi-Higgs-doublet models equipped with global symmetry groups, either exact or softly broken, offer a rich framework for constructions beyond the Standard Model and lead to remarkable phenomenological consequences. Knowing all the symmetry options within each class of models can guide its phenomenological exploration, as confirmed by the vast literature on the two- and three-Higgs-doublet models. Here, we begin a systematic study of finite non-abelian symmetry groups which can be imposed on the scalar sector of the four-Higgs-doublet model (4HDM) without leading to accidental symmetries. In this work, we derive the full list of such non-abelian groups available in the 4HDM that can be constructed as extensions of cyclic groups by their automorphism groups. This list is remarkably restricted but it contains cases which have not been previously studied. Since the methods we develop may prove useful for other classes of models, we present them in a pedagogical manner.
3.Observation of false vacuum decay via bubble formation in ferromagnetic superfluids
Authors:Alessandro Zenesini, Anna Berti, Riccardo Cominotti, Chiara Rogora, Ian G. Moss, Thomas P. Billam, Iacopo Carusotto, Giacomo Lamporesi, Alessio Recati, Gabriele Ferrari
Abstract: In quantum field theory, the decay of an extended metastable state into the real ground state is known as ``false vacuum decay'' and it takes place via the nucleation of spatially localized bubbles. Despite the large theoretical effort to estimate the nucleation rate, experimental observations were still missing. Here, we observe bubble nucleation in isolated and highly controllable superfluid atomic systems, and we find good agreement between our results, numerical simulations and instanton theory opening the way to the emulation of out-of-equilibrium quantum field phenomena in atomic systems.
4.Exploring lepton flavor violation phenomena of the $Z$ and Higgs bosons with unprecedented precision at electron-proton colliders
Authors:Adil Jueid, Jinheung Kim, Soojin Lee, Jeonghyeon Song, Daohan Wang
Abstract: We comprehensively study the potential for discovering lepton flavor violation (LFV) phenomena associated with the $Z$ and Higgs bosons at the LHeC and FCC-he. Our meticulous investigation reveals the remarkable suitability of electron-proton colliders, harnessing advantages such as negligible pileups, minimal QCD backgrounds, and suppressed positron-related backgrounds. In our pursuit of LFV of the $Z$ boson, we employ an innovative indirect probe, utilizing the $t$-channel mediation of the $Z$ boson in the process $p e^- \to j \tau^-$. For LFV in the Higgs sector, we scrutinize direct observations of the on-shell decays of $H\to e^+\tau^-$ and $H\to \mu^\pm\tau^\mp$. Focusing on $H\to e^+\tau^-$ proves highly efficient due to the absence of positron-related backgrounds at electron-proton colliders. Through a dedicated signal-to-background analysis with the boosted decision tree algorithm, we demonstrate that the LHeC with the total integrated luminosity of $1{\,{\rm ab}^{-1}}$ can put significantly lower $2\sigma$ bounds than the HL-LHC with $3{\,{\rm ab}^{-1}}$. Specifically, we find ${\rm{Br}}(Z\to e\tau)< 4.8 \times 10^{-7}$, ${\rm{Br}}(H\to e\tau) <1.72 \times 10^{-4} $, and ${\rm{Br}}(H\to \mu\tau) < 1.0 \times 10^{-4}$. Furthermore, our study uncovers the exceptional precision of the FCC-he in measuring the LFV signatures of the $Z$ and Higgs bosons, which indicates the potential for future discoveries in this captivating field.
5.Configurational entropy and the $N^*(1440)$ Roper resonance in QCD
Authors:G. Karapetyan
Abstract: The electroexcitation of the $N^*(1440)$ Roper resonance, which defines the first radially excited state of the nucleon, is examined within the soft-wall AdS/QCD model. Such excited Fock states are characterized by the leading three-quark component, which determines the main properties of Roper resonance. The differential configurational entropy (DCE) was used in the context of minimal and nonminimal couplings in the nuclear interaction with a gauge vector field for $N^*(1440)$ transition. Comparing the main results with the recent data of the CLAS Collaboration at JLab shows a good agreement on the accuracy of the computed data.
6.Vacuum free energy, quark condensate shifts and magnetization in three-flavor chiral perturbation theory to $\mathcal{O}(p^6)$ in a uniform magnetic field
Authors:Prabal Adhikari, Inga Strümke
Abstract: We study three-flavor QCD in a uniform magnetic field using chiral perturbation theory ($\chi$PT). We calculate the vacuum energy density, quark condensate shifts and the renormalized magnetization to $\mathcal{O}(p^6)$ in the low-energy expansion. We find that the calculation of the vacuum density is greatly simplified by cancellations among two-loop diagrams involving charged mesons. Comparing our results with recent $2+1$-flavor lattice QCD data, we find that the light quark condensate shift at $\mathcal{O}(p^6)$ is in better agreement than the shift at next-to-leading order. We also find that the renormalized magnetization, which is positive definite at next-to-leading order can be either positive or negative at $\mathcal{O}(p^{6})$ due to the uncertainties in the low-energy constants.
7.Energy Loss of Monopolium in a Medium
Authors:Huner Fanchiotti, Carlos A. García Canal, Vicente Vento
Abstract: We study the energy loss of excited monopolium in an atomic medium. We perform a classical calculation in line with a similar calculation performed for charged particles which leads in the non relativistic limit to the Bethe-Bloch formula except for the density dependence of the medium, which we do not consider in this paper. Our result shows that for maximally deformed Rydberg states the ionization of monopolium in a light atomic medium is similar to that of light ions.
8.Exploring non-standard $Hb\bar{b}$ interactions at future electron-proton colliders
Authors:Gholamhossein Haghighat, Reza Jafari, Hamzeh Khanpour, Mojtaba Mohammadi Najafabadi
Abstract: In this paper, we use the charged-current Higgs boson production process at future electron-proton colliders, $e^-p \to H j \nu_e$, with the subsequent decay of the Higgs boson into a $b\bar{b}$ pair, to probe the Standard Model effective field theory with dimension-six operators involving the Higgs boson and the bottom quark. The study is performed for two proposed future high-energy electron-proton colliders, the Large Hadron Electron Collider (LHeC) and the Future Circular Collider (FCC-he) at the center-of-mass energies of 1.3 TeV and 3.46 TeV, respectively. Constraints on the CP-even and CP-odd $Hb\bar{b}$ couplings are derived by analyzing the simulated signal and background samples. A realistic detector simulation is performed and a multivariate technique using the gradient Boosted Decision Trees algorithm is employed to discriminate the signal from background. Expected limits are obtained at $95\%$ Confidence Level for the LHeC and FCC-he assuming the integrated luminosities of 1, 2 and 10 ab$^{-1}$. We find that using 1 ab$^{-1}$ of data, the CP-even and CP-odd $Hb\bar{b}$ couplings can be constrained with accuracies of the order of $10^{-3}$ and $10^{-2}$, respectively, and a significant region of the unprobed parameter space becomes accessible.
1.The $X(6550), X(6900), X(7280)$ resonances as the $nS, cc\bar c\bar c$ states
Authors:A. M. Badalian
Abstract: \date{\today} Within the diquark-antidiquark model the masses of the $0^{++}, cc\bar c\bar c$ resonances are calculated, using the expansion of the four-quark wave function in the set of the hyperspherical functions. The interaction is defined via a universal pair-wise potential, which does not contain fitting parameters. The resulting masses $M_4(nS)$ are shown to be very sensitive to the value of $c-$quark mass, chosen in relativistic string Hamiltonian, and $m_c=1.24, 1.30, 1.43$ (in GeV) are considered. The choice of $m_c$, equal to the current mass, $m_c=1.245$ GeV, yields three $nS~(n_r=0,1,2)$ states in a very good agreement with the masses of the $X(6550), X(6900), X(7287)$ resonances, if the gluon-exchange interaction is totally neglected. This fact indicates on a possible screening of the gluon-exchange interaction inhe $cc\bar c\bar c$ system. For $m_c=1.43$~GeV the ground state mass $M_4(1S)=6557$~MeV is obtained in agreement with experiment only if $\alpha_{\rm V}\cong 0.39(1)$ is used, however, in this case the masses of the $2S, 3S$ radial excitations exceed the masses of $X(6900), X(7280)$ by $\sim 100$~MeV.
2.Explaining the Muon g-2 Anomaly in Deflected AMSB for NMSSM
Authors:Li-Jun Jia, Zhuang Li, Fei Wang
Abstract: We propose to embed the General NMSSM (Next-to-Minimal Supersymmetric Standard Model) into the deflected AMSB (Anomaly Mediated Supersymmetry Breaking) mechanism with Yukawa/gauge deflection contributions. After integrating out the heavy messenger fields, the analytical expressions of the relevant soft SUSY breaking spectrum for General NMSSM at the messenger scale can be calculated. We find that successful EWSB (Electroweak Symmetry Breaking) and realistic low energy NMSSM spectrum can be obtained in some parameter regions. In addition, we find that the muon $g-2$ anomaly and electron $g-2$ anomaly (for positive central value electron $g-2$ experimental data) can be jointly explained to $1\sigma$ and $2\sigma$ range, respectively. The $Z_3$ invariant NMSSM, which corresponds to $\xi_F=0$ in our case, can also jointly explain the muon and electron anomaly to $1\sigma$ and $2\sigma$ range, respectively.
3.CURTAINs Flows For Flows: Constructing Unobserved Regions with Maximum Likelihood Estimation
Authors:Debajyoti Sengupta, Samuel Klein, John Andrew Raine, Tobias Golling
Abstract: Model independent techniques for constructing background data templates using generative models have shown great promise for use in searches for new physics processes at the LHC. We introduce a major improvement to the CURTAINs method by training the conditional normalizing flow between two side-band regions using maximum likelihood estimation instead of an optimal transport loss. The new training objective improves the robustness and fidelity of the transformed data and is much faster and easier to train. We compare the performance against the previous approach and the current state of the art using the LHC Olympics anomaly detection dataset, where we see a significant improvement in sensitivity over the original CURTAINs method. Furthermore, CURTAINsF4F requires substantially less computational resources to cover a large number of signal regions than other fully data driven approaches. When using an efficient configuration, an order of magnitude more models can be trained in the same time required for ten signal regions, without a significant drop in performance.
4.Beyond the Standard Model physics in the far-forward region of the Large Hadron Collider
Authors:Sebastian Trojanowski
Abstract: A new physics program has been initiated as part of the ongoing LHC physics run in the far-forward region, where dedicated FASER and [email protected] experiments are currently taking data. We discuss the possible discovery prospects of this program in the search for signatures of beyond the Standard Model physics. We focus on both the present period and the proposed future Forward Physics Facility (FPF) that will operate in the high luminosity LHC era.
5.Minimal model inspired by family number and dark matter
Authors:Duong Van Loi, Cao H. Nam, Phung Van Dong
Abstract: We consider a gauge symmetry extension of the standard model given by $SU(3)_C\otimes SU(2)_L\otimes U(1)_X\otimes U(1)_N\otimes Z_2$ with minimal particle content, where $X$ and $N$ are family dependent but determining the hypercharge as $Y=X+N$, while $Z_2$ is an exact discrete symmetry. In our scenario, $X$ (while $N$ is followed by $X-Y$) and $Z_2$ charge assignments are inspired by the number of fermion families and the stability of dark matter, as observed, respectively. We examine the mass spectra of fermions, scalars, and gauge bosons, as well as their interactions, in presence of a kinetic mixing term between $U(1)_{X,N}$ gauge fields. We discuss in detail the phenomenology of the new gauge boson and the right-handed neutrino dark matter stabilized by $Z_2$ conservation. We obtain parameter spaces simultaneously satisfying the recent CDF $W$-boson mass, electroweak precision measurements, particle colliders, as well as dark matter observables, if the kinetic mixing parameter is not necessarily small.
6.Exploring light dark matter with the Migdal effect in hydrogen-doped liquid xenon
Authors:Nicole F. Bell, Peter Cox, Matthew J. Dolan, Jayden L. Newstead, Alexander C. Ritter
Abstract: An ongoing challenge in dark matter direct detection is to improve the sensitivity to light dark matter in the MeV--GeV mass range. One proposal is to dope a liquid noble-element direct detection experiment with a lighter element such as hydrogen. This has the advantage of enabling larger recoil energies compared to scattering on a heavy target, while leveraging existing detector technologies. Direct detection experiments can also extend their reach to lower masses by exploiting the Migdal effect, where a nuclear recoil leads to electronic ionisation or excitation. In this work we combine these ideas to study the sensitivity of a hydrogen-doped LZ experiment (HydroX), and a future large-scale experiment such as XLZD. We find that HydroX could have sensitivity to dark matter masses as low as 5~MeV for both spin-independent and spin-dependent scattering, with XLZD extending that reach to lower cross sections. Notably, this technique substantially enhances the sensitivity of direct detection to spin-dependent proton scattering, well beyond the reach of any current experiments.
7.Evolution and interpolation of double parton distributions using Chebyshev grids
Authors:Markus Diehl, Riccardo Nagar, Peter Ploessl, Frank J. Tackmann
Abstract: Double parton distributions are the nonperturbative ingredients needed for computing double parton scattering processes in hadron-hadron collisions. They describe a variety of correlations between two partons in a hadron and depend on a large number of variables, including two independent renormalization scales. This makes it challenging to compute their scale evolution with satisfactory numerical accuracy while keeping computational costs at a manageable level. We show that this problem can be solved using interpolation on Chebyshev grids, extending the methods we previously developed for ordinary single-parton distributions. Using an implementation of these methods in the C++ library ChiliPDF, we study for the first time the evolution of double parton distributions beyond leading order in perturbation theory.
8.Neutrino many-body correlations
Authors:Lucas Johns
Abstract: This paper responds to suggestions that the standard approach to collective neutrino oscillations leaves out potentially important quantum many-body correlations. Arguments in favor of this idea have been based on calculations that, on close scrutiny, offer no evidence either way. Inadequacies of the usual quantum-kinetic formalism are not currently supported by the literature.
1.Cosmic rays from heavy particle decays
Authors:E. V. Arbuzova, A. D. Dolgov, A. A. Nikitenko
Abstract: Multidimensional modification of gravity with a smaller mass scale of the gravitational interaction is considered. Stable by assumption dark matter particles could decay via interactions with virtual black holes. The decay rates of such processes are estimated. It is shown that with the proper fixation of the parameters the decays of these ultra-massive particles can give noticeable contribution to the flux of high energy cosmic rays in particular, near the Greisen-Zatsepin-Kuzmin limit. Such particles can also create neutrinos of very high energies observed in the existing huge underwater or ice-cube detectors.
2.COHERENT production of a Dark Fermion
Authors:Pablo M. Candela, Valentina De Romeri, Dimitrios K. Papoulias
Abstract: We consider the possible production of a new MeV-scale fermion at the COHERENT experiment. The new fermion, belonging to a dark sector, can be produced through the up-scattering process of neutrinos off the nuclei and the electrons of the detector material, via the exchange of a light vector or scalar mediator. We perform a detailed statistical analysis of the combined COHERENT CsI and LAr data sets and obtain up-to-date constraints on the couplings and masses of the dark fermion and mediators. We finally briefly comment about the stability of the dark fermion.
3.Flavor Exotic Triply-Heavy Tetraquark States in AdS/QCD Potential
Authors:Halil Mutuk
Abstract: We study the $S$-wave mass spectra of flavor exotic triply-heavy tetraquark states $cc\bar{c}\bar{q}$, $cc\bar{b}\bar{q}$, $bb\bar{c}\bar{q}$ and $bb\bar{b}\bar{q}$. We adopt a diquark-antidiquark scheme to solve Schr\"{o}dinger equation. The calculations are carried out in a nonrelativistic quark model with a color interaction described by a potential computed in AdS/QCD. The AdS/QCD potential model consists of a central potential which reflects short distance and large distance behaviour of QCD, spin dependent term for hyperfine splitting and a constant term. We find stable state candidates in the $cc\bar{c}\bar{q}$ sector whereas in the $cc\bar{b}\bar{q}$, $bb\bar{c}\bar{q}$ and $bb\bar{b}\bar{q}$ sectors all the states lie above corresponding $S$-wave meson-meson thresholds. \end{abstract}
4.A multi-channel U-Matrix model of hadron interaction at high energy
Authors:Rami Oueslati
Abstract: The present phenomenological study aims at investigating a multi-channel model for hadron interaction at high energy by considering a full parton configuration space, using the U-matrix unitarisation scheme of the elastic amplitude, comparing it to the two-channel model, and examining the consequences of up-to-date high-energy collider data on the best fits to total, elastic, inelastic, and single-diffractive cross sections for $pp$ and $p \bar{p}$ scattering. The results highlight that the data are well-fitted with the multi-channel model. Based on our best fit, predictions for the $\rho$ parameter, the ratio of the real part to the imaginary part of the elastic amplitude, the double diffractive cross-section, and the elastic differential cross-section are provided. We shed light on the effect of taking into account a multi-channel model on present and future cosmic ray data.
5.Impact of the $f$-Reggeon exchanges on the observables of the single diffractive dissociation of nucleon at ultrahigh energies
Authors:A. A. Godizov
Abstract: Single diffractive dissociation (SDD) of nucleon in high-energy proton-proton and proton-antiproton collisions is considered in terms of a simple two-Reggeon model with nonlinear Regge trajectories. It is demonstrated that the $f$-Reggeon impact on the corresponding cross-sections is not negligible up to the LHC energies. As well, it is shown that the account of the $f$-Reggeon exchanges allows to describe the elastic diffractive scattering (EDS) and SDD of nucleons at ultrahigh energies in the framework of a unified phenomenological scheme. The predictive value of the proposed model is verified.
6.Detecting ALP wiggles at TeV energies
Authors:M. Kachelriess, J. Tjemsland
Abstract: Axions and axion-like-particles (ALPs) are characterised by their two-photon coupling, which entails so-called photon-ALP oscillations as photons propagate through a magnetic field. These oscillations lead to distinctive signatures in the energy spectrum of high-energy photons from astrophysical sources, allowing one to probe the existence of ALPs. In particular, photon-ALP oscillations will induce energy dependent oscillatory features, or ``ALP wiggles'', in the photon spectra. We propose to use the discrete power spectrum to search for ALP wiggles and present a model-independent statistical test. By using PKS 2155-304 as an example, we show that the method has the potential to significantly improve the experimental sensitivities for ALP wiggles. Moreover, we discuss how these sensitivities depend on the modelling of the magnetic field. We find that the use of realistic magnetic field models, due to their larger cosmic variance, substantially enhances detection prospects compared to the use of simplified models.
7.Accommodating the H$(650)$ in the HEFT
Authors:Iñigo Asiáin, Domènec Espriu, Federico Mescia
Abstract: Loss of unitarity in an effective field theory is often cured by the appearance of dynamical resonances, revealing the presence of new degrees of freedom. These resonances may manifest themselves when suitable unitarization techniques are implemented in the effective theory, which in the scalar-isoscalar channel require making use of the coupled-channel formalism. Conversely, experimental detection of a resonance may provide interesting information on the couplings and constants of the relevant effective theory. By applying the systematical procedure developed in previous works, we will attempt to accommodate a possible scalar resonance with mass around $650$ GeV for which there is preliminary evidence at the LHC in the vector boson fusion channel. The results are interesting: the resonance can be accommodated within the experimentally allowed range of next-to-leading order coefficients in the HEFT but in a rather non-trivial manner. Interestingly, its width and production cross section turn out to agree with the tentative experimental results.
8.Present and future constraints on flavor-dependent long-range interactions of high-energy astrophysical neutrinos
Authors:Sanjib Kumar Agarwalla, Mauricio Bustamante, Sudipta Das, Ashish Narang
Abstract: The discovery of new, flavor-dependent neutrino interactions would provide compelling evidence of physics beyond the Standard Model. We focus on interactions generated by the anomaly-free, gauged, abelian lepton-number symmetries, specifically $L_e-L_\mu$, $L_e-L_\tau$, and $L_\mu-L_\tau$, that introduce a new matter potential sourced by electrons and neutrons, potentially impacting neutrino flavor oscillations. We revisit, revamp, and improve the constraints on these interactions that can be placed via the flavor composition of the diffuse flux of high-energy astrophysical neutrinos, with TeV-PeV energies, i.e., the proportion of $\nu_e$, $\nu_\mu$, and $\nu_\tau$ in the flux. Because we consider mediators of these new interactions to be ultra-light, lighter than $10^{-10}$ eV, the interaction range is ultra-long, from km to Gpc, allowing vast numbers of electrons and neutrons in celestial bodies and the cosmological matter distribution to contribute to this new potential. We leverage the present-day and future sensitivity of high-energy neutrino telescopes and of oscillation experiments to estimate the constraints that could be placed on the coupling strength of these interactions. We find that, already today, the IceCube neutrino telescope demonstrates potential to constrain flavor-dependent long-range interactions significantly better than existing constraints, motivating further analysis. We also estimate the improvement in the sensitivity due to the next-generation neutrino telescopes such as IceCube-Gen2, Baikal-GVD, KM3NeT, P-ONE, and TAMBO.
9.Single and multi-charmed hadrons from Coalescence: yields and ratios along the system size scan at future LHC
Authors:Vincenzo Minissale Laboratori Nazionali del Sud, INFN-LNS, Via S. Sofia 62, I-95123 Catania, Italy, Salvatore Plumari Laboratori Nazionali del Sud, INFN-LNS, Via S. Sofia 62, I-95123 Catania, Italy Department of Physics and Astronomy "E.Majorana", University of Catania, Via S. Sofia 64, 1-95123 Catania, Italy, Yfeng Sun School of Physics and Astronomy, Shanghai Key Laboratory for Particle Physics and Cosmology, and Key Laboratory for Particle Astrophysics and Cosmology, Vincenzo Greco Laboratori Nazionali del Sud, INFN-LNS, Via S. Sofia 62, I-95123 Catania, Italy Department of Physics and Astronomy "E.Majorana", University of Catania, Via S. Sofia 64, 1-95123 Catania, Italy
Abstract: We study the production of charmed and multi-charmed hadrons in ultra-relativistic Heavy Ion Collisions coupling the transport approach for charm dynamics in the medium to an hybrid hadronization model of coalescence plus fragmentation. In this paper we discuss the particle yields for D mesons and single charmed baryons and the multi-charmed hadrons focusing mainly on the production of $\Xi_{cc}$ and $\Omega_{ccc}$. We provide predictions for PbPb collision in 0-10% centrality class and then we explore the system size dependence through KrKr, to ArAr and OO collisions. In these cases, a monotonic behavior emerges that can be tested in future experimental data. We found about three order of magnitude increase in the production of $\Omega_{ccc}$ in Pb-Pb collisions compared with the yield in small collision systems like OO collisions. Furthermore, we investigate the effects on the $\Omega_{ccc}$ particle production and spectra coming from the modification of the charm quark distribution due to the different size of the collision systems and also in the case of charm thermal distributions. These results suggest that observation on the $\Omega_{ccc}$ spectra and their evolution across system size can give information about the partial thermalization of the charm quark distribution.
10.Hadronic molecules $η_c η_c$ and $χ_{c0}χ_{c0}$
Authors:S. S. Agaev, K. Azizi, B. Barsbay, H. Sundu
Abstract: The fully charmed hadronic scalar molecules $\mathcal{M}_1=\eta_c \eta_c$ and $\mathcal{M}_2=\chi_{c0}\chi_{c0}$ are studied in the context of the QCD sum rule method. The masses $m$, $\widetilde{m}$ and current couplings $f$, $ \widetilde{f}$ of these states are calculated using the two-point sum rule approach. The obtained results $m=(6264 \pm 50)~\mathrm{MeV}$ and $ \widetilde{m}=(6954 \pm 50)~\mathrm{MeV}$ are employed to determine their decay channels. It is demonstrated that the processes $\mathcal{M}_1\to J/\psi J/\psi $ and $\mathcal{M}_1\to \eta _{c}\eta _{c}$ are kinematically allowed decay modes of $\mathcal{M}_1$. The molecule $\mathcal{M}_2$ decays to $ J/\psi J/\psi$, $J/\psi \psi^{\prime}$, $\eta _{c}\eta _{c}$, $\eta _{c}\eta _{c}(2S)$, $\eta _{c}\chi _{c1}(1P)$, and $\chi_{c0} \chi_{c0}$ mesons. The partial widths of all of these processes are evaluated by means of the three-point sum rule calculations, which are necessary to extract the strong couplings $g_i$ at vertices $\mathcal{M}_1J/\psi J/\psi $, $\mathcal{M} _1\eta _{c}\eta _{c}$, and others. Our estimates for the full widths of the molecules $\Gamma_{\mathcal{M}_1}=(320 \pm 72)~\mathrm{MeV}$ and $\Gamma _{ \mathcal{M}_2}=(138 \pm 18)~\mathrm{MeV}$, as well as their masses are compared with parameters of the scalar $X$ resonances discovered by the LHCb-ATLAS-CMS Collaborations in the di-$J/\psi$ and $J/\psi\psi^{\prime}$ invariant mass distributions. We argue that the molecule $\mathcal{M}_1$ can be considered as a real candidate to the scalar resonance $X(6200)$. The structure $\mathcal{M}_2$ may be interpreted as the resonance $X(6900)$ or treated in conjunction with a scalar tetraquark as one of its components.
1.Placing of the recently observed bottom strange state $B_{sJ}(6063)$ and $B_{sJ}(6114)$ in bottom spectra
Authors:Ritu Garg, Pallavi Gupta, A. Upadhyay
Abstract: We have employed HQET to give the spin-parity quantum numbers for recently observed bottom strange states $B_{sJ}(6063)$ and $B_{sJ}(6114)$ by LHCb collaborations. By exploring flavour independent parameters $ \Delta_{F}^{(c)} =\Delta_{F}^{(b)}$ and $ \lambda_{F}^{(c)} = \lambda_{F}^{(b)}$, we calculated masses of experimentally missing bottom strange meson states $2S, 1P, 1D$. We have also analyzed these bottom strange masses by taking ${1/m_Q}$ corrections which lead modifications of parameter terms as $ \Delta_{F}^{(b)} =\Delta_{F}^{(c)} + \delta\Delta_F$ and $ \lambda_{F}^{(b)} = \lambda_{F}^{(c)}\delta\lambda_F$. Further, we have analyzed their two-body decays, couplings, and branching ratios via the emission of light pseudoscalar mesons. Based on predicted masses and decay widths, we tentatively identified the states $B_{sJ}(6063)$ as $2^3S_1$ and $B_{sJ}(6114)$ as $1^3D_1$. Our predictions provide crucial information for future experimental studies.
2.Gravitational freeze-in dark matter from Higgs Preheating
Authors:Ruopeng Zhang, Zixuan Xu, Sibo Zheng
Abstract: Gravitational freeze-in is a mechanism to explain the observed dark matter relic density if dark matter neither couples to inflation nor to standard model sector. In this work, we study gravitational freeze-in dark matter production during Higgs preheating based on non-perturbative resonance. Using reliable lattice method to handle this non-perturbative process, we show that tachyonic resonance is prohibited by strong back reaction due to Higgs self interaction needed to keep the positivity of potential during preheating, and parameter resonance is viable by tuning the Higgs self-interaction coupling to be small enough in ultraviolet energy scale. We then derive the dark matter relic density under the context of Higgs preheating, and uncover a new dark matter parameter space with dark matter mass larger than inflaton mass, which arises from out-of-equilium Higgs annihilation. Finally, we briefly remark the open question of testing gravitational dark matter.
3.Properties of N, $Δ$ Baryons with Screened Potential
Authors:C. Menapara, A. K. Rai
Abstract: N and $\Delta$ baryons hold an important place towards understanding the quark dynamics inside hadrons. The hypercentral Constituent Quark Model (hCQM) has been employed in various studies ranging from light to heavy hadrons. In the present article, screened potential has been used to study light baryon resonances. The Regge trajectories have been plotted alongwith the details of slopes and intercepts. The strong decay widths to pion have been calculated for some channels using the present masses.
4.Probing Dark Matter via Effective Field Theory Approach
Authors:Ayşe Elçiboğa Kuday, Ferhat Özok, Erdinç Ulaş Saka
Abstract: We analyse dark matter in most general form of effective field theory approach. To examine the interactions between weakly interacting massive particles(WIMPs) and Standard Model (SM) particles, we use the six-dimensional EFT mediated by new physics scale $\Lambda$ at tree level. After implementing a new effective field theory model in FeynRules \cite{Feynrules} We investigate the theory and constrain the theory by using relic density generated by MadDM\cite{Maddm} tool of MadGraph5\[email protected] \cite{mg5}.
5.Exotic spin-dependent interactions through unparticle exchange
Authors:L. Y. Wu, K. Y. Zhang, H. Yan
Abstract: The potential discovery of unparticles could have far-reaching implications for particle physics and cosmology. For over a decade, high-energy physicists have extensively studied the effects of unparticles. In this study, we derive six types of nonrelativistic potentials between fermions induced by unparticle exchange in coordinate space. We consider all possible combinations of scalar, pseudo-scalar, vector, and axial-vector couplings to explore the full range of possibilities. Previous studies have only examined scalar-scalar (SS), pseudoscalar-pseudoscalar (PP), vector-vector (VV), and axial-axial-vector (AA) type interactions, which are all parity even. We propose SP and VA interactions to extend our understanding of unparticle physics, noting that parity conservation is not always guaranteed in modern physics. We explore the possibilities of detecting unparticles through the long-range interactions they may mediate with ordinary matter. Dedicated experiments using precision measurement methods can be employed to search for such interactions. We discuss the properties of these potentials and estimate constraints on several coupling constants based on existing experimental data. Our findings indicate that the coupling between vector unparticles and fermions is constrained by up to 9 orders of magnitude more tightly than the previous limits.
6.Axial-vector charges of the spin $\frac{1}{2}^+$ and spin $\frac{3}{2}^+$ light and charmed baryons in the SU(4) chiral quark constituent model
Authors:Harleen Dahiya, Suneel Dutt, Arvind Kumar, Monika Randhawa
Abstract: Following the first clear evidence of the presence of intrinsic charm contribution in the proton, the axial-vector charges of the light and charmed baryons are investigated in the framework of $SU(4)$ chiral constituent quark model after including the explicit contributions from the $u\bar u $, $d\bar d $, $s\bar s $ and $c\bar c $ fluctuations. The axial-vector charges having physical significance correspond to the generators of the $SU(4)$ group with flavor singlet $\lambda^0$, flavor isovector $\lambda^3$, flavor hypercharge $\lambda^8$ and flavor charmed $\lambda^{15}$ combinations of axial-vector current at zero momentum transfer. In contemplation to further understand the $Q^2$ dependence of these charges, we have used the conventionally established dipole form of parametrization. The baryons considered here are the spin $\frac{1}{2}^+$ and spin $\frac{3}{2}^+$ multiplets decomposed further depending on the charm content of baryons.
7.Nuclear corrections on the charged hadron fragmentation functions in a Neural Network global QCD analysis
Authors:Maryam Soleymaninia, Hadi Hashamipour, Hamzeh Khanpour, Samira Shoeib, Alireza Mohamaditabar
Abstract: In this work, we present the new global QCD analyses, referred to as PKHFF.23, for charged pion, kaon, and unidentified light hadrons by utilizing the Neural Network for fitting the high energy lepton-lepton and lepton-hadron scattering to determine parton-to-hadron fragmentation functions (FFs) at both next-to-leading-order (NLO) and next-to-next-to-leading-order (NNLO) accuracy. The analyses include all available single-inclusive $e^+e^-$ annihilation (SIA) and semi-inclusive deep-inelastic scattering (SIDIS) data for charged pions, kaons, and unidentified light hadrons. Considering the most recent nuclear parton distribution functions (nuclear PDFs) available in the literature, we assess the impact of nuclear corrections on the determination of light hadrons FFs. We show that considering the nuclear corrections at both NLO and NNLO accuracy affect the central values of FFs and the associated uncertainty bands, and could improve the fit quality as well. The Neural Network parametrization enriched with the Monte Carlo methodology for uncertainty estimations are used for all sources of experimental uncertainties and the proton PDFs.
8.Generalized parton distributions of $Δ$ resonance in a diquark spectator approach
Authors:Dongyan Fu, Bao-Dong Sun, Yubing Dong
Abstract: The generalized parton distributions (GPDs) for the spin-3/2 $\Delta^+$ resonance are studied numerically by using a diquark spectator approach. Our results show that symmetric constraints from time reversal on GPDs are satisfied. The axial vector form factors of the system are also provided and compared with the lattice QCD calculation. Furthermore, the structure functions are obtained from GPDs in the forward limit. The evolution of structure functions to the scales up to 4 GeV are carried out as predictions for the possible lattice QCD calculations.
9.Radiative corrections to stop-antistop annihilation
Authors:Luca Paolo Wiggering
Abstract: We compute the full $\mathcal{O}(\alpha_s)$ corrections to stop-antistop annihilation into two gluons and a light quark-antiquark pair within the framework of the Minimal Supersymmetric Standard Model (MSSM), including the non-perturbative Sommerfeld enhancement effect. Numerical results for the total annihilation cross section are shown and the effect on the neutralino relic density is discussed for an example scenario in the phenomenological MSSM.
10.Bound state solutions of the Schrödinger equation for dibaryons via asymptotic iteration method
Authors:Nazanin Shiri, Narges Tazimi, Majid Monemzadeh
Abstract: Conventionally, hexaquarks are claimed to be exotic particles, most of which have not yet been experimentally detected. In this work, we study the mass spectra of exotic hadrons known as hexaquarks in the form of dibaryons. We investigate the hexaquark states with the twobody configuration in more detail. Starting from the analytical solution of the radial Schr\"odinger equation for the Hulth\'en potential in the framework of the asymptotic iteration method (AIM), we obtain the binding energy and mass spectrum of charm and bottom hexaquarks for different spin states. We strongly recommend searching experimentally for double charm and bottom dibaryons in the future.
11.Analysis of three-body charmless $B$-meson decays under the factorization-assisted topological-amplitude approach
Authors:Si-Hong Zhou, Xin-Xia Hai, Run-Hui Li, Cai-Dian Lu
Abstract: We analyze quasi-two-body charmless $B$ decays $B_{(s)} \to P_1 V \to P_1 P_2 P_3$ with $V$ representing a vector resonant, and $P_{1,2,3}$ as a light pseudo-scalar meson, pion, kaon or $\eta^{(\prime)}$. The intermediate processes $B_{(s)} \to P_1 V $ are calculated in the factorization-assisted topological-amplitude approach and the vector resonant effects are described by the Breit-Wigner propagator, which successively decay to $P_1 P_2$ via strong interaction. Taking into account of all vector resonances in ground state, $\rho, K^*, \omega, \phi$, we present the related branching fractions, and calculate the virtual effects for $B_{(s)} \to \pi, K (\rho ,\omega \to) KK$. We also predict direct $\it{CP}$ asymmetries of three body B decay modes with $\rho, K^*$ resonances as intermediate states. Our predicted branching fractions of decay modes dominated by the color-favored tree diagram or the color-favored penguin diagram are consistent with the perturbative QCD approach's predictions as well as QCD factorization approach. While for those nonperturbative contribution dominated decay modes, the branching ratios in this work are in better agreement with current experimental data than the PQCD predictions and the QCD factorization results due to their shortage of the nonperturbative contributions or $1/m_b$ power corrections. Many of the decays channels, especially for direct $\it{CP}$ asymmetries, are waiting for the future experiments.
12.Role of $f_0(980)$ and $a_0(980)$ in the $B^- \to π^- K^+ K^- $ and $B^- \to π^- K^0 \bar K^0 $ reactions
Authors:Luciano M. Abreu, Natsumi Ikeno, Eulogio Oset
Abstract: In this work we study the role of the $f_0(980)$ and $a_0(980)$ resonances in the low $ K ^{+} K^{-} $ and $K^0 \bar K^0 $ invariant-mass region of the $B^- \to \pi ^- K^+ K^- $ and $B^- \to \pi ^- K^0 \bar K^0 $ reactions. The amplitudes are calculated by using the chiral unitary $\rm SU(3)$ formalism, in which these two resonances are dynamically generated from the unitary pseudocalar-pseudoscalar coupled-channel approach. The amplitudes are then used as input in the evaluation of the mass distributions with respect to the $ K^{+}K^{-} $ and $ K^{0}\bar K^{0} $ invariant-masses, where the contributions coming from the $I=0$ and $I=1$ components are explicitly assessed. Furthermore, the contribution of the $ K^{\ast }(892)^0 K^- $ production and its influence on the $ \pi^{-} K^+ $ and $ K^{+} K^- $ systems are also evaluated, showing that there is no significant strength for small $ K^{+} K^- $ invariant mass. Lastly, the final distributions of $ M_{\rm inv}^2( K^{\pm}K^{\mp} ) $ for the $B^{\mp} \to \pi ^{\mp} K^{\pm}K^{\mp} $ reactions are estimated and compared with the LHCb data. Our results indicate that the $I=0$ component tied to the $f_0(980)$ excitation generates the dominant contribution in the range of low $ K ^{+} K^{-} $ invariant-mass.
13.Two-component vector WIMP, fermion FIMP dark matter model with an extended seesaw mechanism
Authors:Francesco Costa
Abstract: The document discusses a proposed extension to the Standard Model that aims to explain the presence of neutrino masses and the existence of dark matter. The model includes two potential candidates for dark matter, a vector WIMP and a fermion FIMP, and their combined presence accounts for the total amount of observed dark matter. This study examines the various ways in which dark matter could be produced within this model and explores the connections between the dark matter and neutrino sectors. It also examines various constraints from existing and future experiments. Additionally, the model includes a scalar field that can play a role in a first-order phase transition in the early universe, and the article looks at the potential for the production of gravitational waves as a result of this phase transition and their detectability. This study also assesses the possibility for this phase transition to be strong enough to drive the electroweak baryogenesis.
14.Quarkonium spin alignment in a vortical medium
Authors:Paulo Henrique De Moura, Kayman J. Goncalves, Giorgio Torrieri
Abstract: We use a potential model to investigate the phenomenology of quarkonium in a thermal rotating medium, where vorticity and spin density are not necessarily in equilibrium. We find that the quarkonium spin density matrix, as well as the binding energy and melting temperature, are sensitive to both the vorticity and the lack of equilibrium between vorticity and spin. This means that quarkonium spin alignment is a sensitive probe for vorticity and spin within the hydrodynamic phase. Information unequivocably pointing to spin-orbit non-equilibrium dynamics can be obtained from a combined study of quarkonium relative abundance and spin alignment, as well as experimentally obtainable off-diagonal density matrix elements.
15.anyH3: precise predictions for the trilinear Higgs coupling in the Standard Model and beyond
Authors:Henning Bahl, Johannes Braathen, Martin Gabelmann, Georg Weiglein
Abstract: The trilinear Higgs coupling $\lambda_{hhh}$ of the detected Higgs boson is an important probe for physics beyond the Standard Model. Correspondingly, improving the precision of the theoretical predictions for this coupling as well as the experimental constraints on it are among the main goals of particle physics in the near future. In this article, we present the public $\mathtt{Python}$ code $\mathtt{anyH3}$, which provides precise theoretical predictions for $\lambda_{hhh}$. The program can easily be used for any renormalisable model, where for the input the $\mathtt{UFO}$ format is adopted. It allows including corrections up to the full one-loop level with arbitrary values of the external squared momenta and features a semi-automatic and highly flexible renormalisation procedure. The code is validated against known results in the literature. Moreover, we present new results for $\lambda_{hhh}$ in models which so far have not been investigated in the literature.
16.Dark matter from sterile-sterile neutrino mixing
Authors:Pasquale Di Bari
Abstract: A solution to the problem of the origin of matter in the universe can be reasonably searched within extensions of the standard model that also explain neutrino masses and mixing. Models embedding the minimal seesaw mechanism can explain the observed matter-antimatter asymmetry of the universe via leptogenesis and dark matter via active-sterile neutrino mixing. In this case a keV lightest seesaw neutrino would play the role of warm dark matter particle. This traditional solution is now constrained by various cosmological observations. I will discuss the possibility that a much heavier but yet metastable (dark) right-handed neutrino with mass in the $1\,{\rm TeV}$--$1 \, {\rm PeV}$ range can play the role of (cold) dark matter particle. The right abundance would be produced by the Higgs induced mixing with a seesaw right-handed neutrino (RHINO model), i.e., by sterile-sterile neutrino mixing. Such a mixing would necessarily require a further extension of the minimal seesaw mechanism and can be described by a dimension-five effective operator. The same mixing would also necessarily induce dark neutrino instability with lifetimes that can be much longer than the age of the universe and can escape current constraints from neutrino telescopes. On the other hand, a contribution to very high energy neutrino flux produced by dark neutrino decays could explain an anomalous excess at 100 TeV energies confirmed recently by the IceCube collaboration. I will also discuss a simple UV completion where the mediator is given by a massive fermion. Intriguingly, it comes out that the favoured scale of new physics for RHINO to satisfy the dark matter requirements coincides with the grand-unified scale: a RHINO miracle.
1.Nonlinear corrections for the nuclear gluon distribution in $eA$ processes
Authors:G. R. Boroun, B. Rezaei, F. Abdi
Abstract: An analytical study with respect to the nonlinear corrections for the nuclear gluon distribution function in the next-to-leading order approximation at small $x$ is presented. We consider the nonlinear corrections to the nuclear gluon distribution functions at low values of $x$ and $Q^{2}$ using the parametrization $F_{2}(x,Q^{2})$ and using the nuclear modification factors where they have been obtained with the Khanpour-Soleymaninia-Atashbar-Spiesberger-Guzey model. The CT18 gluon distribution is used as baseline proton gluon density at $Q_{0}^{2}=1.69~\mathrm{GeV}^2$. We discuss the behavior of the gluon densities in the next-to-leading order and the next-to-next-to-leading order approximations at the initial scale $Q_{0}^{2}$, as well as the modifications due to the nonlinear corrections. We find the QCD nonlinear corrections are significant for the next-to-leading order accuracy than the next-to-next-to-leading order for light and heavy nuclei. The results of the nonlinear GLR-MQ evolution equation are similar to those obtained with the Rausch-Guzey-Klasen gluon upward and downward evolutions within the uncertainties. The magnitude of the gluon distribution with the nonlinear corrections increases with a decrease of $x$ and an increase of the atomic number A.
2.Sea contribution to the charge radii and quadrupole moment of $J^P=\frac{1}{2}^+, \frac{3}{2}^+$ baryons
Authors:Preeti Bhall, Meenakshi Batra, Alka Upadhyay
Abstract: An operator formalism is used on the wavefunction of baryons to compute their charge radii and quadrupole moments. Total anti-symmetric wavefunction in spin, color and flavor space is framed for $J^P=\frac{1}{2}^+$ nucleons and $J^P=\frac{3}{2}^+$ hyperons. To understand the importance of sea, statistical model is used in conjugation with the detailed balance principle. Within the statistical approach, the importance of sea with quarks and gluons are studied using the relevant probabilities that are associated with spin, flavor, and color space. The present work also focuses on individual contributions of valence and sea which contains terms of scalar, vector and tensor sea. The obtained results are in agreement with available theories and few experimental outcomes. Our computed results may provide important information for upcoming experimental findings.
3.Gravitational waves from a scotogenic two-loop neutrino mass model
Authors:Cesar Bonilla, A. E. Cárcamo Hernández, João Gonçalves, Vishnudath K. N., António P. Morais, Roman Pasechnik
Abstract: We propose a framework to account for neutrino masses at the two-loop level. This mechanism introduces new scalars and Majorana fermions to the Standard Model. It is assumed the existence of a global $\mathrm{U(1)\times \mathcal{Z}_2}$ symmetry which after partial breaking provides the stability of the dark matter candidates of the theory. The rich structure of the potential allows for the possibility of first-order phase transitions (FOPTs) in the early Universe which can lead to the generation of primordial gravitational waves as one of the potentially observable signatures of this model. Taking into account relevant constraints from lepton flavour violation, neutrino physics as well as the trilinear Higgs couplings at next-to-leading order accuracy, we have found a wide range of possible FOPTs which are strong enough to be probed at the proposed gravitational-wave interferometer experiments such as LISA.
4.On underestimation of the inelastic interactions in the direct dark matter search
Authors:Vadim A. Bednyakov
Abstract: In the paper expressions are obtained for the event rates expected in experiments aimed at direct detection of dark matter (DM) particles. These expressions allow one to estimate the rates taking into account simultaneously elastic (coherent) and inelastic (incoherent) channels of DM particle interaction with nuclei. The nonzero nuclear excitation energies are used in the calculation of the inelastic scattering contributions. A strong correlation between the excitation energy and the recoil energy of the excited nucleus limits the possibility of the inelastic channel detection with a number of nuclei. Together with the standard model of the DM distribution in the Galaxy some models are considered, which allow higher speeds of the DM particle. As the nuclear recoil energy, TA, increases, the dominance of the elastic interaction channel is smoothly replaced by the dominance of the inelastic one. Therefore, if a detector is set up to detect only elastic scattering events, it starts to lose capability of seeing anything. The only way to notice the interaction remains the gamma radiation from the deexcitation of the nucleus. In the case of spin-independent DM interaction, as TA increases, the inelastic contribution quickly dominates. If the DM particle interacts only spin-dependently, the detectors focused on registration of the elastic spin-dependent DM signal will see nothing, since the signal goes through the inelastic channel. It looks like the desired DM interaction could have a noticeable intensity, but the DM detector is unable to detect it. Therefore, a setup aimed at the direct DM detection should register two signals. The first is the nuclear recoil energy and the second is the gamma-quanta with a certain energy from the target nucleus deexitation. The experiment will provide the complete information about the DM interaction.
5.Hydrodynamic effects on the filtered dark matter produced by a first-order phase transition
Authors:Siyu Jiang, Fa Peng Huang, Chong Sheng Li
Abstract: Motivated by current status of dark matter (DM) search, a new type of DM production mechanism is proposed based on the dynamical process of a strong first-order phase transition in the early universe, namely, the filtered DM mechanism. We study the hydrodynamic effects on the DM relic density. By detailed calculations, we demonstrate that the hydrodynamic modes with the corresponding hydrodynamic heating effects play essential roles in determining the DM relic density. The corresponding phase transition gravitational wave could help to probe this new mechanism.
6.Revisiting lifetimes of doubly charmed baryons
Authors:Lovro Dulibić, James Gratrex, Blaženka Melić, Ivan Nišandžić
Abstract: We present updated predictions for lifetimes of doubly charmed baryons, within the heavy quark expansion, including available NLO $\alpha_s$ contributions and newly-computed terms in the $1/m_c$ series. Our results give the hierarchy $$\tau(\Xi_{cc}^{+}) < \tau(\Omega_{cc}^{+}) < \tau(\Xi_{cc}^{++}) \,, $$ while the predicted lifetime $\tau(\Xi_{cc}^{++}) = 0.32 \pm 0.5 ^{+0.8}_{-0.7} \,\textrm{ps} $ is consistent with the recent LHCb determination.
7.Pseudo and quasi quark PDF in the BFKL approximation
Authors:Giovanni Antonio Chirilli
Abstract: I examine the high-energy behavior of the Ioffe-time distribution for the quark bi-local space-like separated operator using the high-energy operator product expansion. These findings have significant implications for lattice calculations, which require extrapolation for large Ioffe-time values. I perform an explicit Fourier transform for both the pseudo-PDF and quasi-PDF, and investigate their behavior within the first two leading twist contributions. I show that the quark pseudo-PDF captures the BFKL resummation (resummation of all twists) and exhibits a rising behavior for small $x_B$ values, while the quasi-PDF presents a different behavior. I demonstrate that an appropriate small-$x_B$ behavior cannot be achieved solely through DGLAP dynamics, emphasizing the importance of all-twist resummation. This study provides valuable insights into quark non-local operators' high-energy behavior and the limitations of lattice calculations in this context.
8.Linear seesaw mechanism from dark sector
Authors:A. E. Cárcamo Hernández, Vishnudath K. N., José W. F. Valle
Abstract: We propose a minimal model where a dark sector seeds neutrino mass generation radiatively within the linear seesaw mechanism. Neutrino masses are calculable, since tree-level contributions are forbidden by symmetry. They are also protected by lepton number symmetry, their smallness arising from small soft breaking terms. Lepton flavour violating processes e.g. $\mu \to e\gamma$ can be sizeable, despite the tiny neutrino masses. We comment also on dark-matter and collider implications.
9.Analysis of Direct and Indirect Detection of Fermionic Dark Matter of 6-Dimensional Effective Field Theory
Authors:Ayşe Elçiboğa Kuday, Ferhat Özok, Erdinç Ulaş Saka
Abstract: We present an analysis of fermionic dark matter (DM) in the context of 6 dimensional Effective Field Theory (EFT). We also compared the result generated via the 6-dimensional EFT analysis with the current experimental results for dark matter searches. These experiments are methodically categorised as direct and indirect search and present some constraints on dark matter model parameters of 6-dimensional EFT. We constructed a new set of tools ensuring DM researches in various platforms. The model parameters are presented to guide DM production in colliders by taking account of the upper limits at direct and indirect searches. In this paper we apply our approach for fermionic case to test the verification of the method. There are various type of search methods for DM, each depends on type of interaction of dark matter with SM particles. Finally we analysed fermionic DM candidate of 6-dimensional Effective Field Theory (EFT) at the platforms of DM searches. A new set of numerical tools is specified for 6-dimensional fermionic DM model, and these tools are also tested.
1.The gauge coupling unification in the flipped $E_8$ GUT
Authors:Konstantin Stepanyantz
Abstract: The gauge coupling unification is investigated at the classical level under the assumptions that the gauge symmetry breaking chain is $E_8\to E_7\times U_1 \to E_6\times U_1 \to SO_{10}\times U_1 \to SU_5 \times U_1 \to SU_3 \times SU_2 \times U_1$ and only components of the representations 248 of $E_8$ can acquire vacuum expectation values. We demonstrate that there are several options for the relations between the gauge couplings of the resulting theory, but the only symmetry breaking pattern corresponds to $\alpha_3=\alpha_2$ and $\sin^2\theta_W=3/8$. Moreover, only for this option the particle content of the resulting theory includes all MSSM superfields. It is also noted that this symmetry breaking pattern corresponds to the case when all representation which acquire vacuum expectation values have the minimal absolute values of the relevant $U_1$ charges.
2.Is the Higgs Boson the Master of the Universe?
Authors:Fred Jegerlehner
Abstract: The discovery of the Higgs particle has yielded a specific value for the mass of the Higgs boson, which, depending on some technical details in the calculation of the $\overline{\mathrm{MS}}$ parameters (relevant for the high energy range) from the physical parameters (measured in low energy range), allows the Standard Model (SM) to hold up to the Planck scale about $\Lambda_{\rm Pl} \sim 10^{19}~{\rm GeV}$. One then has the possibility that the Higgs boson not only provides mass for all SM-particles but very likely also has supplied dark energy that inflated the young universe shortly after the Big Bang. The SM Higgs boson is a natural candidate for the Inflaton, and the Higgs boson decays are able to reheat the universe after inflation. I argue that the structures of the SM evolve naturally from a Planck cutoff medium (ether) and thus find their explanation. That the SM is an emergent structure is also strongly supported by Veltman's derivation of the SM from some general principles, which we can understand as the result of a low-energy expansion. I emphasize the role of the hierarchy problem and the problem of the cosmological constant as causal for the Higgs inflation scenario. After the discovery of the Higgs boson at 125 GeV, and considering the absence of beyond the SM particles at the LHC, a new view on the SM of particle physics and its role in early cosmology has become indispensable. Very likely, the spectacular Higgs discovery turned out to have completed the SM in an unexpected way, revealing it as an inescapable emergence which shapes the early universe.
3.Quantum calculation of axion-photon transition in electromagnetodynamics for cavity haloscope
Authors:Tong Li, Rui-Jia Zhang
Abstract: The Witten effect implies the presence of electric charge of magnetic monople and possible relationship between axion and dyon. The axion-dyon dynamics can be reliably built based on the quantum electromagnetodynamics (QEMD) which was developed by Schwinger and Zwanziger in 1960's. A generic low-energy axion-photon effective field theory can also be realized in the language of ``generalized symmetries'' with higher-form symmetries and background gauge fields. In this work, we implement the quantum calculation of axion-single photon transition rate inside a homogeneous electromagnetic field in terms of the new axion interaction Hamiltonian in QEMD. This quantum calculation can clearly imply the enhancement of conversion rate through resonant cavity in axion haloscope experiments. We also show the promising potentials on the cavity search of new axion-photon couplings in QEMD.
4.Investigating $Z_{cs}(3985)$ and $Z_{cs}(4000)$ exotic states in $Λ_b\to Z^-_{cs}p$ decays
Authors:Yao Yu, Zhuang Xiong, Han Zhang, Bai-Cian Ke, Jia-Wei Zhang, Dong-Ze He, Rui-Yu Zhou
Abstract: We study the $Z_{cs}(3985)$ and $Z_{cs}(4000)$ exotic states in the decays of $\Lambda_b$ baryons through a molecular scenario. In the final state interaction, the $\Lambda_b\to \Lambda_c D_s^{(*)-}$ decays are followed by the $\Lambda_c D_s^{(*)-}$ to $Z^-_{cs}p$ rescatterings via exchange of a $D^{(*)}$ meson. We predict a branching fraction of $(3.1^{+1.4}_{-2.6})\times 10^{-4}$ for $\Lambda_b\to Z^-_{cs}p$, which can be measured in the $\Lambda_b\to J/\psi K^{(*)-}p$ decay. This study provides insights into the nature of exotic hadrons and their production mechanisms, and guides future experimental searches for the $Z_{cs}(3985)$ and $Z_{cs}(4000)$.
5.Model Building by Coset Space Dimensional Reduction Scheme Using Twelve-Dimensional Coset Spaces
Authors:Kento Asai, Joe Sato, Ryosuke Suda, Yasutaka Takanishi, Masaki J. S. Yang
Abstract: We investigate the twelve-dimensional gauge-Higgs unification models with an eight-dimensional coset space. For each model, we apply the coset space dimensional reduction procedure and examine the particle contents of the resulting four-dimensional theory. Then, some twelve-dimensional SO(18) gauge theories lead to models of the SO(10)\times U(1) grand unified theory in four dimensions, where fermions of the Standard Model appear in multiple generations along with scalars that may break the electroweak symmetry. The representations of the obtained scalars and fermions are summarized.
6.From imaginary to real chemical potential QCD with functional methods
Authors:Julian Bernhardt, Christian S. Fischer
Abstract: We investigate the quality of the extrapolation procedure employed in Ref. [1] to extract the crossover line at real chemical potential from lattice data at imaginary potential. To this end we employ a functional approach that does not suffer from the sign problem. We utilize a well-studied combination of lattice Yang--Mills theory with a truncated set of Dyson--Schwinger equations in Landau gauge for $2 + 1$ quark flavors. This system predicts a critical endpoint at moderate temperatures and rather large (real) chemical potential with a curvature comparable to recent lattice extrapolations. We determine the light quark condensate and chiral susceptibility at imaginary chemical potentials and perform an analytic continuation along the lines described in [1]. We find that the analytically continued crossover line agrees very well (within one percent) with the explicitly calculated one for chemical potentials up to about 80 % of the one of the critical end point. The method breaks down in the region where the chiral susceptibility as a function of the condensate cannot any longer be well described by a polynomial.
7.Dynamics in near-threshold $J/ψ$ photoproduction
Authors:D. Winney, C. Fernandez-Ramirez, A. Pilloni, A. N. Hiller Blin, M. Albaladejo, L. Bibrzycki, N. Hammoud, J. Liao, V. Mathieu, G. Montana, R. J. Perry, V. Shastry, W. A. Smith, A. P. Szczepaniak
Abstract: The study of $J/\psi$ photoproduction at low energies has consequences for the understanding of multiple aspects of nonperturbative QCD, ranging from mechanical properties of the proton, to the binding inside nuclei, and the existence of hidden-charm pentaquarks. Factorization of the photon-$c \bar c$ and nucleon dynamics or Vector Meson Dominance are often invoked to justify these studies. Alternatively, open charm intermediate states have been proposed as the dominant mechanism underlying $J/\psi$ photoproduction. As the latter violates this factorization, it is important to estimate the relevance of such contributions. We analyse the latest differential and integrated photoproduction cross sections from the GlueX and $J/\psi$-007 experiments. We show that the data can be adequately described by a small number of partial waves, which we parameterize with generic models enforcing low-energy unitarity. The results suggest a nonnegligible contribution from open charm intermediate states. Furthermore, most of the models present an elastic scattering length incompatible with previous extractions based on Vector Meson Dominance, and thus call into question its applicability to heavy mesons. Our results indicate a wide array of physics possibilities that are compatible with present data and need to be disentangled.
8.Electromagnetic and gravitational local spatial densities for spin-1 systems
Authors:J. Yu. Panteleeva, E. Epelbaum, J. Gegelia, U. -G. Meißner
Abstract: The matrix elements of the electromagnetic current and the energy-momentum tensor for sharply localized states of spin-1 systems are considered. Their interpretation as local spatial densities of various characteristics of the considered system is discussed.
1.Probing the electroweak $4b + \ell + {\rlap{\,/}{E}_T}$ final state in type I 2HDM at the LHC
Authors:Prasenjit Sanyal, Daohan Wang
Abstract: Most of the experimental searches of the non-Standard Model Higgs boson(s) at the LHC rely on the QCD induced production modes. However, in some beyond Standard Model frameworks, the additional Higgs bosons can have fermiophobic behaviour. The type I two Higgs doublet considered here is a perfect example where all the additional Higgs bosons exhibit fermiophobic nature over a large parameter space. Thus the Electoweak productions of these new Higgs bosons are more dominant over the QCD induced processes. In scenarios with light pseuodoscalar ($A$) which is bound to decay dominantly to $b\bar{b}$, even being fermiophobic, the $4b + W$ state via $p p \to H^\pm A \to (AW)A \to 4b + W$ and followed by the leptonic decay of $W$ boson can surpass the QCD initiated $4b$ final state. However, the signal gets overshadowed by large $t\bar{t}+$ jets background and hence constructing a suitable discriminator based on the signal hypothesis and signal topology is necessary. We devised a $\chi^2$ variable as the most suitable signal-background discrimintor to reduce the background by a sizable amount and showed the discovery reach ( $>3\sigma$) of the EW initiated $4b+ \ell + {\rlap{\,/}{E}_T}$ final state at the LHC.
2.Study of singly heavy baryon lifetimes
Authors:Hai-Yang Chen, Chia-Wei Liu
Abstract: We study the inclusive decay widths of singly heavy baryons with the improved bag model in which the unwanted center-of-mass motion is removed. Additional insight is gained by comparing the charmed and bottom baryons. We discuss the running of the baryon matrix elements and compare the results with the non-relativistic quark model (NRQM). While the calculated two-quark operator elements are compatible with the literature, those of the four-quark ones deviate largely. In particular, the heavy quark expansion holds well in the bag model for four-quark operator matrix elements but badly broken in the NRQM. We predict $1-\tau(\Omega_b)/ \tau(\Lambda_b^0) = (8.34\pm2.22)\%$ in accordance with the current experimental value of $(11.5^{+12.2}_{-11.6})\%$ but potentially in tension with $(13.2\pm 4.7)\%$ obtained in the NRQM. We find an excellent agreement between theory and experiment for the lifetimes of bottom baryons. For charmed baryons, the calculated decay widths confirm that the established new hierarchy of $\tau(\Xi_c^+)> \tau(\Omega_c^0) > \tau(\Lambda_c^+)>\tau(\Xi_c^0)$ originates from dimension-7 four-quark operators. We recommend to measure some semileptonic inclusive branching fractions in the forthcoming experiments to discern different approaches. For example, we obtain ${\cal BF} (\Xi_c^+ \to X e^+ \nu_e) = (8.59\pm 0.49)\% $ and ${\cal BF} (\Omega_c^0 \to X e^+ \nu_e) = (1.88\pm 1.69)\% $ in sharp contrast to ${\cal BF} (\Xi_c^+ \to X e^+ \nu_e) =(12.74^{+2.54}_{-2.45})\% $ and ${\cal BF} (\Omega_c^0 \to X e^+ \nu_e) = (7.59^{+2.49}_{-2.24})\% $ found in the NRQM.
3.CKM matrix parameters from an algebra
Authors:Aditya Ankur Patel, Tejinder P. Singh
Abstract: We report a theoretical derivation of the Cabibbo-Kobayashi-Maskawa (CKM) matrix parameters and the accompanying mixing angles. These results are arrived at from the exceptional Jordan algebra applied to quark states, and from expressing flavor eigenstates (i.e. left-chiral states) as superposition of mass eigenstates (i.e. the right-chiral states) weighted by square-root of mass. Flavor mixing for quarks is mediated by the square-root mass eigenstates, and the mass ratios used have been derived in earlier work from a left-right symmetric extension of the standard model. This permits a construction of the CKM matrix from first principles. There exist only four normed division algebras, they can be listed as follows - the real numbers $\mathbb{R}$, the complex numbers $\mathbb{C}$, the quaternions $\mathbb{H}$ and the octonions $\mathbb{O}$. The first three algebras are fairly well known; however, octonions as algebra are less studied. Recent research has pointed towards the importance of octonions in the study of high energy physics. Clifford algebras and the standard model are being studied closely. The main advantage of this approach is that the spinor representations of the fundamental fermions can be constructed easily here as the left ideals of the algebra. Also the action of various Spin Groups on these representations too can be studied easily. In this work, we build on some recent advances in the field and try to determine the CKM angles from an algebraic framework. We obtain the mixing angle values as $\theta_{12}=11.093^o, \theta_{13}=0.172^o, \theta_{23}=4.054^o$. In comparison, the corresponding experimentally measured values for these angles are $13.04^o \pm 0.05^o, 0.201^o \pm 0.011^o, 2.38^o \pm 0.06^o $. The agreement of theory with experiment is likely to improve when running of quark masses is taken into account.
4.Dissociation cross sections of $ψ(3770)$, $ψ(4040)$, $ψ (4160)$, and $ψ(4415)$ mesons with nucleons
Authors:Ruo-Qing Ding, Xiao-Ming Xu, H. J. Weber
Abstract: We study the dissociation of $\psi (3770)$, $\psi (4040)$, $\psi (4160)$, and $\psi (4415)$ mesons in collisions with nucleons, which takes place in high-energy proton-nucleus collisions. Quark interchange between a nucleon and a $c\bar c$ meson leads to the dissociation of the $c\bar c$ meson. We consider the reactions: $pR \to \Lambda_c^+ \bar{D}^0$, $pR \to \Lambda_c^+ \bar{D}^{*0}$, $pR \to \Sigma_c^{++} D^-$, $pR \to \Sigma_c^{++} D^{*-}$, $pR \to \Sigma_c^{+} \bar{D}^0$, $pR \to \Sigma_c^{+} \bar{D}^{*0}$, $pR \to \Sigma_c^{*++} D^-$, $pR \to \Sigma_c^{*++} D^{*-}$, $pR \to \Sigma_c^{*+} \bar{D}^0$, and $pR \to \Sigma_c^{*+} \bar{D}^{*0}$, where $R$ stands for $\psi (3770)$, $\psi (4040)$, $\psi (4160)$, or $\psi (4415)$. A reaction of a neutron and a $c\bar c$ meson corresponds to a reaction of a proton and the $c\bar c$ meson by replacing the up quark with the down quark and vice versa. Transition-amplitude formulas are derived from the $S$-matrix element. Unpolarized cross sections are calculated with the transition amplitudes for scattering in the prior form and in the post form. The cross sections relate to nodes in the radial wave functions of $\psi (3770)$, $\psi (4040)$, $\psi (4160)$, and $\psi (4415)$ mesons.
5.The $B_c$-meson decays into $J/ψ$ plus a light meson in the iPQCD formalism
Authors:Xin Liu
Abstract: In the wake of measurements on $B_c^+ \to J/\psi K^+$, $B_c^+ \to J/\psi \pi^+\pi^-\pi^+$, and $B_c^+ \to J/\psi K^+ K^-\pi^+$ at Large Hadron Collider experiments, we propose to study the decays $B_c^+ \to J/\psi M^+$ comprehensively, with $M$ being the light charged pseudoscalar ($P$), vector ($V$), scalar ($S$), axial-vector ($A$), and tensor ($T$) mesons, within the improved Perturbative QCD (iPQCD) formalism at leading order in the Standard Model. The theoretical predictions for experimental observables such as branching fractions, relative ratios, and longitudinal polarization fractions in the iPQCD formalism await near future examinations relying on the upgraded Large Hadron Collider, even the forthcoming Circular Electron Positron Collider. We emphasize that the investigations on the factorizable-emission-suppressed or -forbidden decays like $B_c^+ \to J/\psi S^+$, $B_c^+ \to J/\psi A^+_{1^1\!P_1}$, and $B_c^+ \to J/\psi T^+$, should go definitely beyond naive factorization to explore the rich dynamics, which could, in turn, further help understand the QCD nature of $B_c$ meson, as well as that of related hadrons. The future confirmations on those predictions about the relative ratios between the branching fractions of $B_c^+ \to J/\psi b_1(1235)^+ (a_0(980)^+, a_0(1450)^+, a_2(1320)^+)$ and $B_c^+ \to J/\psi \pi^+$ could further examine the reliability of this iPQCD formalism. Because of containing only tree-level $\bar b \to \bar c$ transitions, the CP asymmetries in the $B_c^+ \to J/\psi M^+$ decays exhibit naturally zero.
6.Spontaneous magnetization of a vacuum in high temperature gluodynamics (two-loop approximation
Authors:V. Skalozub
Abstract: In SU(N) gluodynamics, at high temperature the spontaneous magnetization, b(T) not equal to 0, of a vacuum happens in the approximation to the effective potential - the tree plus the one-loop, plus daisy diagrams, W(b)= b^2/2 g^2 + W^(1)(b) + W^(daisy)(b). At the same time, in two-loop approximation, W(A_0)= W^(1)(A_0) + W^(2)(A_0), other classical field - A_0 condensate directly related to the Polyakov loop - is also spontaneously generated. To investigate the creation of the condensates together, the two loop effective potential of both fields should be calculated. This program was realized recently for SU(2) in [1]. However, the generation of magnetic field in two-loop order was not studied in detail. In the present paper, we compute the value of chromomagnetic field b(T) for latter case. Then, considering the spectrum of color charged gluons at the background of both condensates, we conclude that the A_0 stabilizes the magnetized vacuum at high temperature. This is in agreement with the lattice simulations carried out already and clarifies the mechanism of the magnetic field stabilization.
7.Invisible Decays of a Non-SM-like $H_2$ to Dark Matter in the N2HDM and the NMSSM
Authors:Maien Binjonaid King Saud University
Abstract: We investigate two extensions of the standard model that include particle dark matter candidates: the N2HDM and the NMSSM. These models feature a non-SM-like CP-even scalar with a sub-TeV mass, denoted by $H_2$, among other particles. At a 13 TeV proton-proton collider, the primary production channel for such scalars is via the fusion of a pair of gluons. Subsequently, these scalars can decay invisibly into a pair of dark matter candidates, with some regions of the parameter space exhibiting a dominance of such decay over other modes. In the supersymmetric model, it is possible for the LSP and NLSP to be mass degenerate, leading to quasi-invisible $H_2$ decays to LSP+NLSP and NLSP+NLSP. We present the predictions of both models for this challenging scenario while ensuring compatibility with recent experimental constraints.
8.Baryon-meson scattering amplitude at tree level in the $1/N_c$ expansion
Authors:Ruben Flores-Mendieta, Johann Hernandez
Abstract: The baryon-meson scattering amplitude is computed at tree level within the $1/N_c$ expansion of QCD, where $N_c$ is the number of color charges. The most general expression is obtained by accounting for explicitly the effects of the decuplet-octet baryon mass difference. Although the resultant expression is general enough that it can be applied to any incoming and outgoing baryons and mesons, provided that the Gell-Mann--Nishijima scheme is respected, results for nucleon-pion scattering processes are explicitly dealt with. With these, some isospin relations are verified to be valid at the physical value $N_c=3$. Corrections due to $SU(3)$ flavor symmetry breaking are only sketched so they are left for future work. The three-level expressions obtained here represent a first effort toward understanding scattering processes in the context of the $1/N_c$ expansion.
9.The high-energy QCD dynamics from Higgs-plus-jet correlations at the FCC
Authors:Francesco Giovanni Celiberto, Alessandro Papa
Abstract: Recent analyses on high-energy inclusive Higgs-boson rates in proton collisions via the gluon-fusion channel, matched with the state of-the-art fixed-order N$^3$LO accuracy, have shown that the impact of high-energy resummation corrections reaches 10% at the FCC nominal energies. This supports the statement that electroweak physics at 100 TeV is expected to receive relevant contributions from small-$x$ physics. In this preliminary study we present novel predictions for transverse-momentum and rapidity distributions sensitive to the inclusive emission of a Higgs boson in association with a light-flavored jet in proton collisions, calculated within the NLL accuracy of the energy-logarithmic resummation. We highlight how high-energy signals for this process are already present and visible at current LHC energies, and they are also sizable at the FCC ones. We come out with the message that the improvement of fixed-order calculations on Higgs-sensitive QCD distributions is a core ingredient to reach the precision level in the description of observables relevant for the Higgs physics at the FCC.
10.MLAnalysis: An open-source program for high energy physics analyses
Authors:Yu-Chen Guo, Fan Feng, An Di, Shi-Qi Lu, Ji-Chong Yang
Abstract: We present a python-based program for phenomenological investigations in particle physics using machine learning algorithms, called \verb"MLAnalysis". The program is able to convert LHE and LHCO files generated by \verb"[email protected]" into data sets for machine learning algorithms, which can analyze the information of the events. At present, it contains three machine learning (ML) algorithms: isolation forest (IF) algorithm, nested isolation forest (NIF) algorithm, kmeans anomaly detection (KMAD), and some basic functionality to analyze the kinematic features of a data set. Users can use this program to improve the efficiency of searching for new physics signals.
1.Conserved number fluctuations under global rotation in a hadron resonance gas model
Authors:Gaurav Mukherjee, Dipanwita Dutta, Dipak Kumar Mishra
Abstract: Net-charge, net-strangeness and net-baryon number fluctuations measured in ultra-relativistic heavy-ion collisions may reveal details and insights into the quark-hadron transition, hadrochemical freeze-out and possibly aid in the search of the QCD critical point. By controlling the collision energy, some current and upcoming heavy-ion facilities aim to study high energy nucleus-nucleus collisions in the finite net-baryon density regime where the effects of rapid global rotation are also expected to be strong for the peripheral collisions. We discuss the ratios of conserved number susceptibilities that are experimentally measurable via products of the moments of the corresponding distributions and compute the relevant theoretical results in the framework of a rotating hadron resonance gas (rHRG) model.
2.Building models of quarks and gluons with an arbitrary number of colors using Cartan-Polyakov loops
Authors:Renan Câmara Pereira, Pedro Costa
Abstract: In this work we introduce the concept of Cartan-Polyakov loops, a special subset of Polyakov loops in the fundamental representation of the $\mathrm{SU}(N_c)$ group, with charges $k=1,\ldots,(N_c-1)/2$. They constitute a sufficient set of independent degrees of freedom to parametrize the thermal Wilson line. Using properties of the characteristic polynomial of the thermal Wilson line, we write a non-Cartan-Polyakov loop charge decomposing formula. This formalism allows one to readily build effective models of quarks and gluons with an arbitrary number of colors. We apply it to the Polyakov$-$Nambu$-$Jona-Lasinio model and to an effective glue model, in the mean field approximation, showing how to directly extend these models to higher values of $N_c$.
3.Baryon-rich QCD matter
Authors:Jochen Wambach
Abstract: Properties of high-density strong-interaction matter of relevance for astrophysical scenarios that involve neutron stars are discussed. It is argued that theoretical and experimental insights from the small baryo-chemical potential ($\mu_B$) and high-temperature regions of the QCD phase diagram can guide realistic model building at high density, as this regime is currently not accessible to first-principles numerical calculations of the QCD partition function. Special attention is payed to the chiral properties of high-density matter and the nature of a possible first-order chiral phase transition. In this transition hadronic parity-partners, in particular baryons, become spectrally degenerate with finite (pole) masses, as expected from general insight into the mass generation in QCD. Possible signals in heavy-ion dielectron production at beam energies of a few GeV are discussed. Based on evidence for an emergent "chiral spin symmetry" above the pseudo-critical chiral transition temperature at small $\mu_B$, speculations on the physical state of dense hadronic matter beyond the chiral phase transition are presented.
4.Molecular charmed baryons and pentaquarks from light-meson exchange saturation
Authors:Mao-Jun Yan, Fang-Zheng Peng, Manuel Pavon Valderrama
Abstract: The spectrum of the $c qq$ baryons contains a few states whose nature is not clearly a three-quark composite and which might have a sizable baryon-meson component. Examples include the $\Sigma_c(2800)$ or the $\Lambda_c(2940)$. Here we explore the spectrum of two-body systems composed of a light, octet baryon and a charmed meson (or antimeson) within a simple contact-range theory in which the couplings are saturated by light-meson exchanges. This results in the prediction of a series of composite anticharmed pentaquarks ($\bar{c} q qqq $) and singly-charmed baryons ($c \bar{q} qqq $). Among the later we find $J=\tfrac{1}{2}$ $\Xi D$ and $J=\tfrac{3}{2}$ $\Xi D^*$ bound states with masses matching those of the recently observed $\Omega_c(3185)$ and $\Omega_c(3327)$ baryons.
5.Exotic fully heavy pentaquarks in bag model
Authors:Wen-Xuan Zhang, Hong-Tao An, Duojie Jia
Abstract: Inspired by the observation of a resonant state $X(6600)$ of fully charm tetraquark by the CMS experiment of LHCb Collaboration in double $J/\psi $ decay channel, we perform a systematical study of all configurations of fully heavy pentaquarks $P_{Q_{1}Q_{2}Q_{3}Q_{{4}}\bar{Q_{5}}}$ ($Q_{i}=c,b,$ $i=1,2,3,4,5$) in their ground states in unified framework of MIT bag model. The color-spin wavefunctions of pentaquarks, classified via Young tableau and presented in terms of the Young-Yamanouchi bases, are used to compute masses and magnetic moments of fully heavy pentaquarks via numerical variational method, predicting a set of masses ranging from $8.229$ GeV for the $P_{cccc\bar{c}}$ to $24.770$ GeV for the $P_{bbbb\bar{b}}$.Combining with computed masses of fully heavy mesons and baryons, we find that masses of fully heavy hadrons(mesons, baryons, tetraquarks and pentaquarks) with identical flavor rise almost linearly with the number of valence quarks in hadrons, being consistent with the heavy quark symmetry in the heavy-quark limit.
6.A contact interaction model for the $η$ and $η'$ mesons in a SDE-BSE approach to QCD: masses, decay widths and transition form factors
Authors:Bilgai Almeida Zamora, Enrique Carreon Martínez, Jorge Segovia, J. J. Cobos-Martínez
Abstract: We construct a contact interaction model for the $\eta$ and $\eta'$ mesons in the SDE-BSE approach to QCD and compute several static properties of these mesons and their transition form factors. We find that this model gives an excellent description of the $\eta$ and $\eta'$ static properties, namely their masses, decay width and decay constants. However, a contact interaction disagrees with experimental data for $Q^2$ greater than 2 GeV$^2$, and produces transition form factors in conflict with perturbative QCD prediction. This is not surpring and the reasons for this are explained
7.Flow Away your Differences: Conditional Normalizing Flows as an Improvement to Reweighting
Authors:Malte Algren, Tobias Golling, Manuel Guth, Chris Pollard, John Andrew Raine
Abstract: We present an alternative to reweighting techniques for modifying distributions to account for a desired change in an underlying conditional distribution, as is often needed to correct for mis-modelling in a simulated sample. We employ conditional normalizing flows to learn the full conditional probability distribution from which we sample new events for conditional values drawn from the target distribution to produce the desired, altered distribution. In contrast to common reweighting techniques, this procedure is independent of binning choice and does not rely on an estimate of the density ratio between two distributions. In several toy examples we show that normalizing flows outperform reweighting approaches to match the distribution of the target.We demonstrate that the corrected distribution closes well with the ground truth, and a statistical uncertainty on the training dataset can be ascertained with bootstrapping. In our examples, this leads to a statistical precision up to three times greater than using reweighting techniques with identical sample sizes for the source and target distributions. We also explore an application in the context of high energy particle physics.
1.The strong vertices of charmed mesons $D$, $D^{*}$ and charmonia $J/ψ$, $η_{c}$
Authors:Jie Lu, Guo-Liang Yu, Zhi-Gang Wang
Abstract: In this work, the strong form factors and coupling constants of the vertices $DDJ/\psi$, $DD^{*}J/\psi$, $D^{*}D^{*}J/\psi$, $DD^{*}\eta_{c}$, $D^{*}D^{*}\eta_{c}$ are calculated within the framework of the QCD sum rule. For each vertex, we analyze the form factor considering all possible off-shell cases and the contributions of the vacuum condensate terms $\langle\overline{q}q\rangle$, $\langle\overline{q}g_{s}\sigma Gq\rangle$, $\langle g_{s}^{2}G^{2}\rangle$, $\langle f^{3}G^{3}\rangle$ and $\langle\overline{q}q\rangle\langle g_{s}^{2}G^{2}\rangle$. Then, the form factors are fitted into analytical functions $g(Q^2)$ and are extrapolated into time-like regions to get the strong coupling constants. Finally, the strong coupling constants are obtained by using on-shell cases of the intermediate mesons($Q^2=-m^2$). The results are as follows, $g_{DDJ/\psi}=5.33^{+0.57}_{-0.45}$, $g_{DD^{*}J/\psi}=4.02^{+0.36}_{-0.24}$GeV$^{-1}$, $g_{D^{*}D^{*}J/\psi}=5.98^{+0.61}_{-0.58}$, $g_{DD^{*}\eta_{c}}=4.05^{+0.42}_{-0.13}$ and $g_{D^{*}D^{*}\eta_{c}}=5.73^{+0.49}_{-0.47}$GeV$^{-1}$.
2.Baryogenesis from sphaleron decoupling
Authors:Muzi Hong, Kohei Kamada, Jun'ichi Yokoyama
Abstract: The electroweak sphaleron process breaks the baryon number conservation within the realms of the Standard Model of particle physics (SM). Recently, it is pointed out that its decoupling may provide the out-of-equilibrium condition required for baryogenesis. In this paper, we study such a scenario taking into account the baryon-number wash-out effect of the sphaleron itself to improve the estimate. We clarify the amount of CP violation required for this scenario to explain the observed asymmetry.
3.Lepton flavor physics at $μ^+ μ^+$ colliders
Authors:Kåre Fridell, Ryuichiro Kitano, Ryoto Takai
Abstract: We discuss sensitivities to lepton flavor violating (and conserving) interactions at future muon colliders, especially at $\mu^+\mu^+$ colliders. Compared with the searches for rare decays of $\mu$ and $\tau$, we find that the TeV-scale future colliders have better sensitivities depending on the pattern of hierarchy in the flavor mixings. As an example, we study the case with the type-II seesaw model, where the flavor mixing parameters have direct relation to the neutrino mass matrix. At a $\mu^+ \mu^+$ collider, the number of events of the $\mu^+ \mu^+ \to \mu^+ \tau^+$ process can be larger than $\mathcal{O}(100)$ with the center of mass energy $\sqrt s = 2$ TeV, and with an integrated luminosity ${\cal L} = 1$ ab$^{-1}$, while satisfying bounds from rare decays of $\mu$ and $\tau$. We discuss impacts of the overall mass scale of neutrinos as well as CP violating phases to the number of expected events.
4.The resonant probing spin-0 and spin-2 dark matter mediators with fixed target experiments
Authors:I. V. Voronchikhin, D. V. Kirpichnikov
Abstract: We discuss the mechanism to produce electron-specific dark matter mediators of spin-0 and spin-2 in the electron fixed target experiments such as NA64 and LDMX. The positrons produced by the electromagnetic shower can produce the regarding mediators via annihilation on atomic electrons. That mechanism, for some selected kinematics, results in the enhanced sensitivity with respect to the bounds derived by the bremsstrahlung-like emission of the mediator in the specific parameter space. We derive the regarding experimental reach of the NA64 and LDMX.
5.Constructing all the matrix elements of covariant tensor currents of massless particles in the covariant formulation
Authors:Jaehoon Jeong
Abstract: We present an efficient algorithm for constructing all the matrix elements of covariant tensor currents of massless particles of arbitrary spins in the covariant formulation. This algorithm enables us to construct all the covariant three-point vertices simply by assembling the basic building blocks, leading to the construction of the matrix elements. We revisit the closely-related two restrictions on massless particles called the Landau-Yang (LY) and Weinberg-Witten (WW) theorems for the massless particles of arbitrary spins. We find the covariance conditions on form factors causing the corresponding tensor currents to be covariant and verify that the continuity assumption of matrix elements taken in the original paper discussing the WW theorem is correct at least in the quantum field theory including conventional massless fields. By invoking a simple example, we show that in general the matrix elements given in the covariant formulation cannot cover all the covariant tensor currents fully.
6.Analysis of the decay $Y(4500)\to D^*\bar{D}^*π$ with the light-cone QCD sum rules
Authors:Zhi-Gang Wang
Abstract: In this work, we tentatively assign the $Y(4500)$ as the $[uc]_{\tilde{A}}[\overline{uc}]_{V}+[uc]_{V}[\overline{uc}]_{\tilde{A}}+[dc]_{\tilde{A}}[\overline{dc}]_{V} +[dc]_{V}[\overline{dc}]_{\tilde{A}}$ tetraquark state with the quantum numbers $J^{PC}=1^{--}$, and study the three-body strong decay $Y(4500)\to D^{*-}D^{*0}\pi^+$ with the light-cone QCD sum rules. It is the first time to use the light-cone QCD sum rules to calculate the four-hadron coupling constants, the approach can be extended to study other three-body strong decays directly and diagnose the $X$, $Y$ and $Z$ states.
7.Exploring the flavor structure of quarks and leptons with reinforcement learning
Authors:Satsuki Nishimura, Coh Miyao, Hajime Otsuka
Abstract: We propose a method to explore the flavor structure of quarks and leptons with reinforcement learning. As a concrete model, we utilize a basic policy-based algorithm for models with $U(1)$ flavor symmetry. By training neural networks on the $U(1)$ charges of quarks and leptons, the agent finds 21 models to be consistent with experimentally measured masses and mixing angles of quarks and leptons. In particular, an intrinsic value of normal ordering tends to be larger than that of inverted ordering, and the normal ordering is well fitted with the current experimental data in contrast to the inverted ordering. A specific value of effective mass for the neutrinoless double beta decay and a sizable leptonic CP violation induced by an angular component of flavon field are predicted by autonomous behavior of the agent.
8.Mass corrections to the energy loss of a heavy fermion in a hot plasma
Authors:Marc Comadran, Cristina Manuel, Stefano Carignano
Abstract: We evaluate the collisional energy loss of a energetic fermion with mass $M$ propagating through a hot QED plasma with temperature $T$, including mass corrections, that is, keeping the mass $m$ of the fermion constituents of the plasma, assuming $m \ll T \ll M$. We use the bare theory to compute the contribution of hard momentum transfer collisions, and the Braaten-Pisarski resummed theory, amended with small mass corrections, for the contribution of low momentum transfer collisions, and compute the mass corrections at leading logarithmic accuracy in the regime where the energy of the heavy fermion obeys $E \ll M^2/T$. We use dimensional regularization to regulate all possible divergences in the computation. If the fermion mass is of order of the soft scale $eT$, where $e$ is the gauge coupling constant, the mass corrections are of the same order as pure perturbative corrections, while they can be substantial for larger values of $m$. We also evaluate the impact of this correction for a QCD plasma.
9.Entropy from entangled parton states and high-energy scattering behavior
Authors:Hans Gunter Dosch, Guy F. de Teramond, Stanley J. Brodsky
Abstract: The relation between the gluon density in a hadron and entanglement entropy can shed a new light on the high energy scattering behavior of hadrons: The growth above the classical geometric cross section is directly related to the increase of the internal quantum entropy from the entangled parton distribution in hadrons. A rather consistent picture emerges from the scale dependence of the Pomeron from the QCD evolution of the gluon distribution function $g(x, \mu)$, the rising of the integrated cross section in photoproduction of vector mesons, hadron multiplicity and entropy.
10.The trouble with the minimal renormalizable SO(10) GUT
Authors:Kateřina Jarkovská, Michal Malinský, Vasja Susič
Abstract: We scrutinize the physical viability of the minimal non-supersymmetric $\mathrm{SO}(10)$ GUT with the scalar sector $\mathbf{45}\oplus\mathbf{126}\oplus\mathbf{10}_{\mathbb{C}}$, in which the unified symmetry is broken by the former two representations, and a realistic Yukawa sector is supported by the last two. Alongside the known issue of a relatively low GUT scale (and thus overly fast proton decay) encountered in minimally fine-tuned scenarios, we identify a very general problem of the model: the inability to properly accommodate a Standard-Model-like low-energy Higgs doublet in the perturbative regime.
11.A Modern Global Extraction of the Sivers Function
Authors:I. P. Fernando, D. Keller
Abstract: Deep Neural Networks (DNNs) are a powerful and flexible tool for information extraction and modeling. In this study, we use DNNs to extract the Sivers functions by globally fitting Semi- Inclusive Deep Inelastic Scattering (SIDIS) and Drell-Yan (DY) data. To make predictions of this Transverse Momentum-dependent Distribution (TMD), we construct a minimally biased model using data from COMPASS and HERMES. The resulting Sivers function model, constructed using SIDIS data, is also used to make predictions for DY kinematics specific to the valence and sea quarks, with careful consideration given to experimental errors, data sparsity, and complexity of phase space.
12.Reduction to master integrals via intersection numbers and polynomial expansions
Authors:Gaia Fontana, Tiziano Peraro
Abstract: Intersection numbers are rational scalar products among functions that admit suitable integral representations, such as Feynman integrals. Using these scalar products, the decomposition of Feynman integrals into a basis of linearly independent master integrals is reduced to a projection. We present a new method for computing intersection numbers that only uses rational operations and does not require any integral transformation or change of basis. We achieve this by systematically employing the polynomial series expansion, namely the expansion of functions in powers of a polynomial. We also introduce a new prescription for choosing dual integrals, de facto removing the explicit dependence on additional analytic regulators in the computation of intersection numbers. We describe a proof-of-concept implementation of the algorithm over finite fields and its application to the decomposition of Feynman integrals at one and two loops.
1.Determination of neutrino mass ordering from Supernova neutrinos with T2HK and DUNE
Authors:Papia Panda, Monojit Ghosh, Rukmani Mohanta
Abstract: In this paper we study the possibility of determining the neutrino mass ordering from the future supernova neutrino events at the DUNE and T2HK detectors. We estimate the expected number of neutrino event rates from a future supernova explosion assuming GKVM flux model corresponding to different processes that are responsible for detecting the supernova neutrinos at these detectors. We present our results in the form of $\chi^2$, as a function of supernova distance. For a systematic uncertainty of 5\%, our results show that, the neutrino mass ordering can be determined at $5 ~\sigma$ C.L. if the supernova explosion occurs at a distance of 44 kpc for T2HK and at a distance of 6.5 kpc for DUNE. Our results also show that the sensitivity of T2HK gets affected by the systematic uncertainties for the smaller supernova distances. Further, we show that in both DUNE and T2HK, the sensitivity gets deteriorated to some extent due to presence of energy smearing of the neutrino events. This occurs because of the reconstruction of the neutrino energy from the energy-momentum measurement of the outgoing leptons at the detector.
2.Exploring CP-violation in $Y=0$ inert triplet with real singlet
Authors:Shilpa Jangid, Hiroshi Okada
Abstract: In this article, we examine the Standard Model extended with a $Y=0$ Higgs triplet and a real singlet. We consider the Higgs triplet to be odd under the $Z_2$ symmetry, and hence the lightest stable particle from the inert triplet becomes the dark matter candidate, whereas the real singlet is considered to be even under the $Z_2$ symmetry. A dimension-5 effective term is introduced with the help of a real singlet, which breaks the CP symmetry and gives an additional source of CP-violation in the fermion sector. The phase transition proceeds in two-steps, with the symmetry breaking in the singlet direction occurring first and later leading to the usual electroweak symmetry breaking minima, while electroweak baryogenesis is associated with the second step. The parameters chosen for the electroweak phase transition are found to be consistent with the Planck scale stability and the perturbativity using two-loop $\beta$-functions. The DM mass bound for inert triplet, i.e., 1.2 TeV (below which it is under abundance), also comes out to be consistent with the strongly first-order phase transition, which was not possible solely with inert triplet. The upper bound on the triplet mass comes out to be $\leq 3.8$ TeV, which satisfies the strongly first-order phase transition. This particular benchmark point also satisfies the correct baryon asymmetry of the Universe $(6.13 \times 10^{-11})$, and the gravitational wave spectrum also lies within the detectable frequency range of LISA $(6.978 \times 10^{-4} - 1.690 \times 10^{-2} )$ Hz and BBO $(2.80\times 10^{-3}-1.096)$ Hz experiments.
3.Muon anomalous magnetic dipole moment in a low scale type I see-saw model
Authors:D. N. Dinh
Abstract: Recent experimental results on muon anomalous magnetic dipole moment have shown a $4.2\sigma$ tension with the SM prediction, which has blown a fresh wind into the elementary particle physics community. The problem is believed to be explained only by physics beyond the standard model. Current work considers the anomalous moment in a scenario of models with mirror symmetry and type I see-saw mechanism at low energy scale of electroweak interactions. After a brief introduction to the model, a detailed numerical analysis of muon anomalous phenomenology will be carefully performed.
4.Quark and lepton model with flavor specific dark matter and muon $g-2$ in modular $A_4$ and hidden $U(1)$ symmetries
Authors:Takaaki Nomura, Hiroshi Okada
Abstract: We propose a quark and lepton model explaining their masses, mixings, and CP violating phases, introducing modular $A_4$ and hidden gauged $U(1)$ symmetries. The hidden $U(1)$ brings us heavier Majorana fermions that are requested by chiral anomaly cancellations, and we work on a canonical seesaw scenario due to their neutral particles.In this framework, we search for favorite parameter space to satisfy both the experimental values and show predictions, applying the $\chi$ square analysis.Then, we discuss a bosonic dark matter candidate that only annihilates into muon state due to the modular $A_4$ flavor symmetry where we suppose the main interaction of dark matter to be Yukawa terms. And we study muon anomalous magnetic dipole moment where there are not any constraints of lepton flavor violations thanks to this flavor symmetry. Finally, we show the allowed space to satisfy the observed relic density of dark matter and the muon anomalous magnetic dipole moment.
5.Rational Function Simplification for Integration-by-Parts Reduction and Beyond
Authors:Kirill Mokrov, Alexander Smirnov, Mao Zeng
Abstract: We present FUEL (Fractional Universal Evaluation Library), a C++ library for performing rational function arithmetic with a flexible choice of third-party computer algebra systems as simplifiers. FUEL is an outgrowth of a C++ interface to Fermat which was originally part of the FIRE code for integration-by-parts (IBP) reduction for Feynman integrals, now promoted to be a standalone library and with access to simplifiers other than Fermat. We compare the performance of various simplifiers for standalone benchmark problems as well as IBP reduction runs with FIRE.
6.Neutrino Oscillations by a Manifestly Coherent Mechanism and Massless vs. Massive Neutrinos
Authors:Anca Tureanu
Abstract: The neutrino oscillations in vacuum are derived in a manifestly coherent scheme. The mechanism is operative in a quantum field theoretical framework, justifying nevertheless a formal analogy with quantum mechanical two- (or more) level systems and their oscillatory behaviour. Both the flavour states and the massive states are eigenstates of certain Hamiltonians which, in special conditions, can be argued to share the same Hilbert space. In this scheme, flavour neutrinos are massless and play the role of asymptotic states for any interactions, including the weak interactions, while massive neutrinos are effective propagation states. The vacuum is interpreted as a medium, where the flavour neutrinos undergo coherent forward scatterings which modify their energy and mix their flavour. The treatment of matter conversion and MSW effect fits in naturally; the extension to other neutral particle oscillations, like $K_0-\bar K_0$, is straightforward. The scheme is eclectic insofar as it combines seamlessly quantum field theory and quantum mechanics.
7.Fingerprinting the Type-Z three Higgs doublet models
Authors:Rafael Boto, Dipankar Das, Luis Lourenco, Jorge C. Romao, Joao P. Silva
Abstract: There has been great interest in a model with three Higgs doublets in which fermions with a particular charge couple to a single and distinct Higgs field. We study the phenomenological differences between the two common incarnations of this so-called Type-Z 3HDM. We point out that the differences between the two models arise from the scalar potential only. Thus we focus on observables that involve the scalar self-couplings. We find it difficult to uncover features that can uniquely set apart the $Z_3$ variant of the model. However, by studying the dependence of the trilinear Higgs couplings on the nonstandard masses, we have been able to isolate some of the exclusive indicators for the $Z_2\times Z_2$ version of the Type-Z 3HDM. This highlights the importance of precision measurements of the trilinear Higgs couplings.
8.Heavy- and light-flavor symmetry partners of the $T_{cc}^+(3875)$, the $X(3872)$ and the $X(3960)$ from light-meson exchange saturation
Authors:Fang-Zheng Peng, Mao-Jun Yan, Manuel Pavon Valderrama
Abstract: The spectrum of the charmed meson-(anti)meson system is a fundamental tool for disentangling the nature of a few exotic hadrons, including the recently discovered $T_{cc}^+(3875)$ tetraquark, the $X(3960)$, or the $X(3872)$, the nature of which is still not clear after almost two decades of its discovery. Here we consider that the charmed meson-(anti)meson short-range interaction is described by the exchange of light-mesons ($\sigma$, $\rho$, $\omega$). The effects of light-meson exchanges are recast into a simple contact-range theory by means of a saturation procedure, resulting in a compact description of the two-hadron interaction. From this, if the $T_{cc}^+$ were to be an isoscalar $D^* D$ molecule, then there should exist an isoscalar $J=1$ $D^* D^*$ partner, as constrained by heavy-quark spin symmetry. Yet, within our model, the most attractive two charmed meson configurations are the isovector $J=0$ $D^* D^*$ molecule and its sextet $D_s^* D^*$ and $D_s^* D_s^*$ flavor partners. Finally, we find a tension between the molecular descriptions of the $T_{cc}^+$ and that of the $X(3872)$ and $X(3960)$, where most parameter choices suggest that if the $T_{cc}^+$ is purely molecular then the $X(3872)$ overbinds (or conversely, if the $X(3872)$ is a molecule the $T_{cc}^+$ does not bind). This might be consequential for determining the nature of these states.
9.Linking Resonant leptogenesis with dynamics of the inverse seesaw theory with $ A_{4} $ flavor symmetry
Authors:Maibam Ricky Devi, Kalpana Bora
Abstract: In this paper, we analyse resonant leptogenesis in a low scale inverse seesaw model with $A_4$ flavor symmetry, in a model we explored earlier to explain light neutrino masses and mixings, and also charged lepton flavor violating decay $\mu\rightarrow e\gamma$. Six $ A_{4} $ scalar singlets and one $ A_{4} $ fermion triplet are included, which are charged under the group $A_{4}\times U(1)_{X} \times Z_{5} \times Z_{4} $, with at least two degenerate RH (Right Handed) neutrinos. The light neutrino masses and leptogenesis both share a same origin with the heavy right handed neutrinos. Thus, we expound the possibility of generating resonant leptogenesis in this model at energies as low as 1 TeV. We then analyse our findings to envision if our model inclines more towards weak or strong washout.
10.Determination of meson fragmentation functions in the Field-Feynman model
Authors:Qiaomu Peng, Bo-Qiang Ma
Abstract: We study the fragmentation functions of both pions and kaons in the Field-Feynman recursive model with the extended SU(2) flavor symmetry relations of fragmentation functions and fitting parameters. Parametrizations are determined from a leading-order (LO) analysis of HERMES experimental multiplicity data of meson production in semi-inclusive deep inelastic scattering, and uncertainties are estimated with the Hessian method. We compare our results with the experimental data and the analysis results of other parametrizations. The SU(2) flavor symmetry breaking effect of meson fragmentation functions of $ud$ quarks is also discussed, and we show that the fragmentation functions of kaons have a bigger SU(2) flavor symmetry breaking effect of $ud$ quarks than these of pions.
11.Asymptotic Analysis on Binned Likelihood and Neutrino Floor
Authors:Jian Tang, Bing-Long Zhang
Abstract: Observations of suspected coherent elastic neutrino-nucleus scatterings by dark matter direct detection experiments highlight the need for an investigation into the so-called ``neutrino floor". We focus on the discovery limit, a statistical concept to identify the neutrino floor, and analyze the asymptotic behaviour of the profile binned likelihood ratio test statistic where the likelihood is constructed by variate from events in each bin and pull terms from neutrino fluxes. To achieve the asymptotic result, we propose two novel methods: i) Asymptotic-Analytic method, which furnishes the analytic result for large statistics, is applicable for more extra nuisance parameters, and enables the identification of the most relevant parameters in the statistical analysis; ii) Quasi-Asimov dataset, which is analogous to Asimov dataset but with improved speed. Applying our methods to the neutrino floor, we significantly accelerate the computation procedure compared to the previous literature, and successfully address cases where Asimov dataset fails. Our derivation on the asymptotic behavior of the test statistic not only facilitates research into the impact of neutrinos on the search for dark matter, but may also prove relevant in similar application scenarios.
1.Non-thermal Higgs Spectrum in Reheating Epoch: Primordial Condensate vs. Stochastic Fluctuation
Authors:Kunio Kaneta, Kin-ya Oda
Abstract: Since electroweak symmetry is generally broken during inflation, the Standard Model Higgs field can become supermassive even after the end of inflation. In this paper, we study the non-thermal phase space distribution of the Higgs field during reheating, focusing in particular on two different contributions: primordial condensate and stochastic fluctuations. We obtain their analytic formulae, which agree with the previous numerical result. As a possible consequence of the non-thermal Higgs spectrum, we discuss perturbative Higgs decay during reheating for the case it is kinematically allowed. We find that the soft-relativistic and hard spectra are dominant in the decay rate of the stochastic fluctuation and that the primordial condensate and stochastic fluctuations decay almost at the same time.
2.Enhanced Four-Body Decays of Charged Higgs Bosons into Off-Shell Pseudoscalar Higgs and $W^\pm$ Boson Pairs in a Lepton-Specific 2-Higgs Doublet Model
Authors:Stefano Moretti, Muyuan Song
Abstract: We study the time-honoured decay $H^\pm\to A W^\pm$ but for the first time, we do so for the case of both $A$ and $W^\pm$ being off-shell, therefore computing a $1\to 4$ body decay. We show that the corresponding decay rate not only extends the reach of $H^\pm$ searches to small masses of the latter but also that the results of our implementation differ significantly from the yield of the $1\to3$ body decay over the phase space region in which the latter is normally used. We show the phenomenological relevance of this implementation in the case of the so-called lepton-specific 2-Higgs Doublet Model (2HDM) over the mass region wherein the aforementioned $1\to 4$ body decay can dominate just beyond the top (anti)quark mass. This mass region is accessible in the lepton-specific 2HDM as the Yukawa couplings are such that limits from $b \to s \gamma$ and $\tau \to \mu \nu_{\tau} \bar{\nu_\mu}$ observables on $M_{H^\pm}$ are rather mild. However, we emphasise that similar effects may occur in other 2HDM types, as the $W^\pm H^\mp A$ vertex is 2HDM type independent.
3.An Augmented QCD Phase Portrait: Mapping Quark-Hadron Deconfinement for Hot, Dense, Rotating Matter under Magnetic Field
Authors:Gaurav Mukherjee, D. Dutta, D. K. Mishra
Abstract: The quark-hadron transition that happens in ultra-relativistic heavy-ion collisions is expected to be influenced by the effects of rotation and magnetic field, both present due to the geometry of a generic non-head-on impact. We augment the conventional $T$--$\mu_B$ planar phase diagram for QCD matter by extending it to a multi-dimensional domain spanned by temperature $T$, baryon chemical potential $\mu_B$, external magnetic field $B$ and angular velocity $\omega$. Using two independent approaches, one from a rapid rise in entropy density and another dealing with a dip in the squared speed of sound, we identify deconfinement in the framework of a modified statistical hadronization model. We find that the deconfinement temperature $T_C(~\mu_B,~\omega,~eB)$ decreases nearly monotonically with increasing $\mu_B,~\omega $ and $ eB $ with the most prominent drop (by nearly $40$ to $50$ MeV) in $T_C$ occurring when all the three quasi-control (collision energy and centrality) parameters are simultaneously tuned to finite values that are typically achievable in present and upcoming heavy-ion colliders.
4.More Synergies from Beauty, Top, $Z$ and Drell-Yan Measurements in SMEFT
Authors:Cornelius Grunwald, Gudrun Hiller, Kevin Kröninger, Lara Nollen
Abstract: We perform a global analysis of Beauty, Top, $Z$ and Drell-Yan measurements in the framework of the Standard Model effective theory (SMEFT). We work within the minimal flavor violation (MFV) hypothesis, which relates different sectors and generations beyond the $SU(2)_L$-link between left-handed top and beauty quarks. We find that the constraints on the SMEFT Wilson coefficients from the combined analysis are stronger than the constraints from a fit to the individual sectors, highlighting synergies in the global approach. We also show that constraints within MFV are strengthened compared to single-generation fits. The strongest bounds are obtained for the semileptonic four-fermion triplet operator $C_{lq}^{(3)}$, probing scales as high as $18$ TeV, followed by the gluon dipole operator $C_{uG}$ with $7$ TeV, and other four-fermion and penguin operators in the multi-TeV range. Operators with left-handed quark bilinears receive order one contributions from higher orders in the MFV expansion induced by the top Yukawa coupling as a result of the FCNC $b \to s \mu \mu$ anomalies combined with the other sectors. We predict the $68\%$ credible intervals of the dineutrino branching ratios within MFV as $5.3 \cdot 10^{-6} \leq {\cal{B}}(B^0 \to K^{* 0} \nu \bar\nu) \leq 12.8 \cdot 10^{-6}$ and $ 2.5 \cdot 10^{-6} \leq {\cal{B}}(B^+ \to K^+ \nu \bar\nu) \leq 5.9 \cdot 10^{-6}$, which include the respective Standard Model predictions, and are in reach of the Belle II experiment. We show how future measurements of the dineutrino branching ratios can provide insights into the structure of new physics in the global fit.
5.Small $x$ Physics Beyond Eikonal Approximation: an Effective Hamiltonian Approach
Authors:Ming Li
Abstract: Understanding the spin structure of hadrons in the small $x$ regime is an important direction to unravel the spin puzzle in hadronic physics. To include spin degrees of freedom in the small $x$ regime requires going beyond the usual eikonal approximation in high energy QCD. We developed an effective Hamiltonian approach to study spin related observables in the small $x$ regime using the shockwave formalism. The small-$x$ effective Hamiltonian incorporates both quark and gluon propagators in the background fields and the background field induced interaction vertices up to next-to-eikonal order. A novel feature of sub-eikonal interactions is the background gluon field induced gluon radiation inside the shockwave. Its relation to chromo-electrically polarized Wilson line correlator is established both in small $x$ helicity evolution and in longitudinal double-spin asymmetry for gluon production.
6.Tagging a Boosted Top quark with a $τ$ final state
Authors:Amit Chakraborty, Amandip De, Rohini M. Godbole, Monoranjan Guchait
Abstract: Boosted top quark tagging is one of the challenging, and at the same time exciting, tasks in high energy physics experiments, in particular in the exploration of new physics signals at the LHC. Several techniques have already been developed to tag a boosted top quark in its hadronic decay channel. Recently tagging the same in the semi-leptonic channel has begun to receive a lot of attention. In the current study, we develop a methodology to tag a boosted top quark ($p_T>$ 200 GeV) in its semi-leptonic decay channel with a $\tau$-lepton in the final state. In this analysis, the constituents of the top fatjet are reclustered using jet substructure technique to obtain the subjets, and then $b$- and $\tau$- like subjets are identified applying standard $b$- and $\tau$-jet tagging algorithms. We show that the dominant QCD background can be rejected effectively using several kinematic variables of these subjects, such as energy sharing among the jets, invariant mass, transverse mass, Nsubjettiness etc., leading to high signal tagging efficiencies. We further assess possible improvements in the results by employing multivariate analysis techniques. We find that using this proposed top-tagger, a signal efficiency of $\sim 77\%$ against a background efficiency of $\sim 3\%$ can be achieved. We also extend the proposed top-tagger to the case of polarized top quarks by introducing a few additional observables calculated in the rest frame of the $b-\tau$ system. We comment on how the same methodology will be useful for tagging a boosted heavy BSM particle with a $b$ and $\tau$ in the final state.
7.Automated choice of the best renormalization scheme
Authors:S. Heinemeyer, F. von der Pahlen
Abstract: High-precision predictions in BSM models require calculations at the loop-level and thus a renormalization of (some of) the BSM parameter. Here many choices for the renormalization scheme (RS) are possible. A given RS can be well suited to yield ``stable'' and ``well behaved'' higher-order corrections in one part of the BSM parameter space, but can fail completely in other parts. The latter may not even be noticed numerically if an isolated parameter point is investigated. Here we review a new method for choosing a ``well behaved'' RS. We demonstrate the feasibility of our new method in the chargino/neutralino sector of the Minimal Supersymmetric Standard Model (MSSM), but stress the general applicability of our method to all types of BSM models.
8.Production rates of dark photons and $Z'$ in the Sun and stellar cooling bounds
Authors:Shao-Ping Li, Xun-Jie Xu
Abstract: Light weakly interacting particles could be copiously produced in the Sun which, as a well-understood star, could provide severe constraints on such new physics. In this work, we calculate the solar production rates of light gauge bosons (e.g. dark photon) arising from various $U(1)$ extensions of the standard model. It is known that the dark photon production rate is suppressed by the dark photon mass if it is well below the plasmon mass of the medium. We show that for more general $U(1)$ gauge bosons, this suppression is absent if the couplings are not in alignment with those of the photon. We investigate a few frequently discussed $U(1)$ models including $B-L$, $L_{\mu}-L_{\tau}$, and $L_{e}-L_{\mu(\tau)}$, and derive the stellar cooling bounds for these models.
1.Imprint of PBH domination on gravitational waves generated by cosmic strings
Authors:Debasish Borah, Suruj Jyoti Das, Rishav Roshan, Rome Samanta
Abstract: We study the effect of an ultra-light primordial black hole (PBH) dominated phase on the gravitational wave (GW) spectrum generated by a cosmic string (CS) network formed as a result of a high-scale $U(1)$ symmetry breaking. A PBH-dominated phase leads to tilts in the spectrum via entropy dilution and generates a new GW spectrum from PBH density fluctuations, detectable at ongoing and planned near-future GW detectors. The combined spectrum has a unique shape with a plateau, a sharp tilted peak over the plateau, and a characteristic fall-off, which can be distinguished from the one generated in the combination of CS and any other matter domination or new exotic physics. We discuss how ongoing and planned future experiments can probe such a unique spectrum for different values of $U(1)$ breaking scale and PBH parameters such as initial mass and energy fraction.
2.Charmless Semileptonic Baryonic $B_{u,d,s}$ Decays
Authors:Chun-Khiang Chua
Abstract: We study $\bar B_q\to {{\rm\bf B}\bar{\rm\bf B}}' l \bar\nu$ and $\bar B_q\to {{\rm\bf B}\bar{\rm\bf B}}' \nu \bar\nu$ decays with all low lying octet and decuplet baryons using a topological amplitude approach. In tree induced $\bar B_q\to {{\rm\bf B}\bar{\rm\bf B}}' l \bar\nu$ decay modes, we need 2 tree and 1 annihilation amplitudes in octet-anti-octet decay modes, 1 tree amplitude in octet-anti-decuplet decay modes, 1 tree amplitude in decuplet-anti-octet decay modes and 1 tree and 1 annihilation amplitudes in decuplet-anti-decuplet decay modes. In loop induced $\bar B_q\to {{\rm\bf B}\bar{\rm\bf B}}' \nu \bar\nu$ decay modes, similar numbers of penguin-box and penguin-box-annihilation amplitudes are needed. Relations on these semileptonic baryonic $B_q$ decay amplitudes are found. Furthermore, the ratios of loop topological amplitudes and tree topological amplitudes are fixed by known CKM factors and loop functions. The observed $B^-\to p\bar p \mu^-\bar\nu$ differential rate exhibits threshold enhancement, which is expected to hold in all other semileptonic baryonic modes. The threshold enhancement squeezes the phase space and leads to very large SU(3) breaking effects in the decay rates. They are estimated using the measured $B^-\to p\bar p \mu^-\bar\nu$ differential rate and model calculations. Modes with relatively unsuppressed rates and good detectability are identified. These modes can be searched experimentally in near future and the rate estimations can be improved when more modes are discovered. Ratios of rates of some loop induced $\bar B_q\to {{\rm\bf B}\bar{\rm\bf B}}' \nu \bar\nu$ decays and tree induced $\bar B_q\to {{\rm\bf B}\bar{\rm\bf B}}' l \bar\nu$ decays are predicted and can be checked experimentally. They can be tests of the SM.
3.The Hierarchy Problem and the Top Yukawa
Authors:Andreas Bally, Yi Chung, Florian Goertz
Abstract: In this talk, an alternative to top partner solutions and its consequences on phenomenology are discussed. The hierarchy problem from the top loop contribution is solved by mitigating the top Yukawa coupling at high scales. In this scenario, the new degrees of freedom appearing at the cut-off scale of the top loop should then be some new top-philic particles instead of traditional top partners. The idea can be directly tested through measurements in top physics, including $t\bar{t}h$, $t\bar{t}$ differential cross section, and $t\bar{t}t\bar{t}$ cross section.
4.QCD bound states in motion
Authors:Paul Hoyer
Abstract: I consider the frame dependence of QCD bound states in the presence of a confining, spatially constant gluon field energy density. The states are quantized at equal time in $A^0=0$ (temporal) gauge. I derive the frame dependence of the wave functions, and demonstrate the Lorentz covariance of the electromagnetic (transition) form factors for states of any spin. The wave functions of $J^{PC}=0^{-+}$ states with CM momentum $P \neq 0$ are considered in some detail, verifying their local normalizability and the expected frame dependence of the bound state energy.
5.Investigating the impact of extra resonance states in the van der Waals Hadron Resonance Gas Model
Authors:Nachiketa Sarkar
Abstract: We investigate, in addition to the experimentally established hadrons, how the inclusion of extra resonance states, through the Hagedorn mass spectrum (HS) or Quark Model (QM) predicated states, affects the thermodynamic and transport quantities of the hadronic system in the van der Waals hadron resonance gas (VDWHRG) model. We found that the VDWHRG model with the HS provides the most accurate description of the lattice QCD results, both at zero and finite chemical potential. Moreover, the inclusion of these extra states has a significant impact on the van der Waals (VDW) parameters, which, in turn, affect the thermodynamic and transport quantities as well as the likely position of the liquid-gas phase transition critical point in the QCD phase diagram. Additionally, we infer that there is a strong correlation between the van der Waals parameters and the chemical potential. Overall, our study sheds light on the importance of considering extra resonance states and proper tuning of the VDW parameters in the VDWHRG model to enhance the accuracy and reliability of the model in the context of Ultra-relativistic heavy-ion physics.
6.Electroweak superpartner production at 13.6 TeV with Resummino
Authors:J. Fiaschi, B. Fuks, M. Klasen, A. Neuwirth
Abstract: Due to the greater experimental precision expected from the currently ongoing LHC Run 3, equally accurate theoretical predictions are essential. We update the documentation of the Resummino package, a program dedicated to precision cross section calculations for the production of a pair of sleptons, electroweakinos, and leptons in the presence of extra gauge bosons, and for the production of an associated electroweakino-squark or electroweakino-gluino pair. We detail different additions that have been released since the initial version of the program a decade ago, and then use the code to investigate the impact of threshold resummation corrections at the next-to-next-to-leading-logarithmic accuracy. As an illustration of the code we consider the production of pairs of electroweakinos and sleptons at the LHC for centre-of-mass energies ranging up to 13.6 TeV and in simplified model scenarios. We find slightly increased total cross section values, accompanied by a significant decrease of the associated theoretical uncertainties. Furthermore, we explore the dependence of the results on the squark masses.
7.Diquark and chiral condensate in a self-consistent NJL-type model
Authors:Wen-Li Yuan, Jingyi Chao, Ang Li
Abstract: In this work, a modified NJL-type model is used, in which the contact current-current interaction is Fierz-transformed into quark-antiquark interactions $\mathcal{F}_{\bar{q} q}=(\bar{q} \hat{O} q)^{2}$ and quark-quark interactions $\mathcal{F}_{q q}=(q \hat{O} q)^{2}$, which are directly related to the chiral condensate and diquark condensate, respectively. Under mean-field approximation, the chiral condensate and the diquark condensate are studied on the same footing. We discuss in detail the competition between the chiral condensate and the diquark condensate, as well as the order of the chiral phase transition by analyzing the resulting chiral susceptibility.
8.Rare charm quark decays in light front approach
Authors:Hang Liu, Chang Yang
Abstract: In this study, we investigate the nonleptonic decays of heavy baryons \Xi^0_c induced by the c\to u (d \bar{d})/ (s \bar{s}) transition. Utilizing the factorization assumption, hadronic form factors are calculated within the light-front quark model. We employ helicity amplitudes to analyze the nonleptonic decay modes of heavy baryons and derive benchmark results for partial decay widths and branching fractions. Our calculations suggest that the branching fractions for some of these rare nonleptonic decays are at the order of 10^ {-5} or 10^ {-6}, which are likely to be detectable at experiments such as LHCb or Belle-II. The potential data accumulated in the future may help to further our understanding of the decay mechanism in the presence of heavy quarks.
1.Hunting scalar partners of the Higgs boson at the LHC
Authors:Werner Porod
Abstract: Composite Higgs models with a fermionic ultraviolet completion predict in general additional pseudo Nambu Goldstone bosons beside the Higgs multiplet. In this contribution we discuss their LHC signatures and present first bounds in simplified models which can also be applied to generic models like multi-Higgs models. We then demonstrate how these can be combined taking a concrete model based on the SU(5)/SO(5) coset as an example. We use this to show how a proper combination of different channels can lead to an improved bound compared to a single channel analysis.
2.eHIJING: an Event Generator for Jet Tomography in Electron-Ion Collisions
Authors:Weiyao Ke, Yuan-Yuan Zhang, Hongxi Xing, Xin-Nian Wang
Abstract: We develop the first event generator, the electron-Heavy-Ion-Jet-Interaction-Generator (eHIJING), for the jet tomography study of electron-ion collisions. In this generator, energetic jet partons produced from the initial hard scattering undergo multiple collisions with the nuclear remnants with a collision rate that is proportional to the transverse-momentum-dependent (TMD) gluon densities in the nucleus. Medium-modified QCD parton splittings within the higher-twist and generalized higher-twist framework are utilized to simulate parton showering in the nuclear medium that takes into account the non-Abelian Landau-Pomeranchuck-Midgal interference in gluon radiation induced by multiple scatterings. The TMD gluon distribution inside the nucleus is given by a simple model inspired by the physics of gluon saturation. Employing eHIJING, we revisit hadron production in semi-inclusive deep inelastic scattering (SIDIS) as measured by EMC, HERMES as well as recent CLAS experiments. eHIJING with both the higher-twist and generalized higher-twist framework gives reasonably good descriptions of these experimental data. Predictions for experiments at the future electron-ion colliders are also provided. It is demonstrated that future measurements of the transverse momentum broadening of single hadron spectra can be used to map out the two dimensional kinematic ($Q^2, x_B$) dependence the jet transport parameter $\hat{q}$ in cold nuclear matter.
3.Running anomalous dimensions in holographic QCD: from the proton to the sexaquark
Authors:Nick Evans, Matthew Ward
Abstract: In holographic models of QCD, the running of the anomalous dimension of the quark bilinear operator leads to chiral symmetry breaking when gamma=1 and the Breitenlohner-Freedman bound is violated. In that case, the running drives the sigma meson mass tachyonic inducing the chiral symmetry breaking. Here we include the running anomalous dimension in the computation of the spectrum of bound states associated with other operators made of light quarks, such as the nucleon and exotic sexaquark states. We show that including the one loop gauge theory running can have substantial effects on the predictions. For example, the nucleon mass to rho mass ratio is improved and lies much closer to the observed value. A similar result is obtained for the Lambda and Xi baryons when strange quarks are included. A uuddss sexaquark state with a low enough mass to make it stable can be achieved, but this depends on the input assumptions about the running dimension.
4.Effects of clustered nuclear geometry on the anisotropic flow in O--O collisions at the LHC within a multiphase transport model framework
Authors:Debadatta Behera, Suraj Prasad, Neelkamal Mallick, Raghunath Sahoo
Abstract: To understand the true origin of flow-like signatures and applicability of hydrodynamics in small collision systems, effects of soft QCD dynamics, the sensitivity of jet-like correlations, and non-equilibrium effects, efforts are being made to perform \textit{p}--O and O--O collisions at the LHC and RHIC energies. It is equally interesting to look into the possible signatures of an $\alpha$--clustered nuclear geometry in $^{16}$O--$^{16}$O collisions by studying the initial-state effects on the final-state observables. In this work, within a multiphase transport model, we implement an $\alpha$--cluster tetrahedral density profile in the Oxygen nucleus along with the default Woods-Saxon density profile. We study the eccentricity ($\epsilon_2$), triangularity ($\epsilon_3$), normalized symmetric cumulants (NCS(2,3)), elliptic flow ($v_2$), and triangular flow ($v_3$) in $^{16}$O--$^{16}$O collisions at $\sqrt{s_{\rm NN}} = 7~$TeV. The constituent quark number scaling of the elliptic flow is also reported. For the most central collisions, enhanced effects in $\langle \epsilon_3 \rangle/ \langle \epsilon_2 \rangle$ and $\langle v_3 \rangle/ \langle v_2 \rangle$ with a negative value of NSC(2,3), and an away-side broadening in the two-particle azimuthal correlation function ($C(\Delta \phi)$) of the identified particles are observed in the presence of an $\alpha$--clustered geometry.
5.Analysis and study of the hidden-charm pentaquark states based on magnetic moment and transition magnetic moment
Authors:Fei Guo, Hao-Song Li
Abstract: In this work, we calculate magnetic moments and transition magnetic moments of the $P^{N^{0}}_{\psi}$ states in molecular model, diquark-diquark-antiquark model and diquark-triquark model, whose isospin doublet state $P^{N^{+}}_{\psi}$ has been observed in the LHCb Collaboration in recent years. Our results show that in the diquark-diquark-antiquark model, the magnetic moments of $\lambda $ excitation state are usually larger than the magnetic moments of $\rho $ excitation state. We find some interesting proportional relationships between the expressions of transition magnetic moments. The results provide important insights for future experimental observation of $P^{N^{0}}_{\psi}$ states and help to distinguish their inner structures. With these efforts, our understanding of the properties for the hidden-charm pentaquark states will become more abundant.
6.Multi-skyrmion states in the Skyrme model with false vaccum potential
Authors:Jun-Shuai Wang, Yong-Liang Ma
Abstract: We study the multi-skyrmion states using a Skyrme model with false vacuum potential upto baryon number $B=8$ using the product ansatz. It is found that, both the false vacuum potential and true vacuum potential can yield cluster structure of the multi-skyrmion states. The effect of the explicit chiral breaking on the masses and the contour surfaces of the baryon number density of the multi-skyrmion states are analyzed.
7.Dilaton photoproduction in a magnetic dipole field of pulsars and magnetars
Authors:Mikhail Astashenkov
Abstract: According to Einstein-Maxwell-Dilaton theory, the dilaton field $\psi$ can be produced by electromagnetic fields with non-zero Maxwell invariant. So electromagnetic wave propagating in an external electromagnetic field is a typical source of dilaton radiation. For study dilaton photoproduction in astrophysical conditions it's interesting to consider plane elliptically polarized electromagnetic wave propagating in the electromagnetic field of magnetic dipole ${\bf m}$ of pulsars and magnetars. The dilation field equation is solved in case $|\psi| \ll 1$. The angular distribution dilaton radiation is studied in every point of space. It's shown that spectral composition of dilatons is similar to spectral composition of plane electromagnetic wave. Amount of dilaton energy radiated in time and all directions is greatest in condition $(B_1^2-B_2^2)(m_x^2-m_y^2)\geq 0,$ where $B_1$ and $B_2$ are electromagnetic wave amplitudes along the axes of polarization ellipse. This condition is valid for many neutron star systems.
8.CP asymmetry from resonance effect of B meson decay process with $π$ and K final states
Authors:Gang Lü, Xi-Liang Yuan, Na-Wang, Xin-Heng Guo
Abstract: We introduce the new resonance of $V\rightarrow K^{+}K^{-}$ $(V=\phi, \rho, \omega)$, which produces some new strong phase associated with vector meson resonance and thus can cause relatively large CP asymmetry at the range of interferences. There are the resonances of $\phi \rightarrow K^{+}K^{-}$, $\rho \rightarrow K^{+}K^{-}$ and $\omega \rightarrow K^{+}K^{-}$ due to the mixing of vector mesons $\phi$, $\rho$, $\omega$. We calculate the CP asymmetry from the decay modes of $B \rightarrow KK\pi(K)$. Meanwhile, the localised CP asymmetries are presented and some detailed analysis can be found. The CP asymmetry from the decay mode of ${B}^{-}\rightarrow \phi\pi^{-}\rightarrow K^{+}K^{-}\pi^{-}$ is also presented in our framework which is well consisted with LHC experiment. The introduced CP asymmetry can provide a favorable theoretical support for the experimental exploration in the future.
9.Inclusive production of fully-charmed tetraquarks at LHC
Authors:Feng Feng, Yingsheng Huang, Yu Jia, Wen-Long Sang, De-Shan Yang, Jia-Yue Zhang
Abstract: The $X(6900)$ resonance, originally discovered by the \texttt{LHCb} collaboration and later confirmed by both \texttt{ATLAS} and \texttt{CMS} experiments, has sparked broad interests in the fully-charmed tetraquark states. Relative to the mass spectra and decay properties of fully-heavy tetraquarks, our knowledge on their production mechanism is still rather limited. In this work we investigate the inclusive production of fully-charmed $S$-wave tetraquarks at \texttt{LHC} within the nonrelativistic QCD (NRQCD) factorization framework. The partonic cross sections are computed at lowest order in $\alpha_s$ and velocity, while the long-distance NRQCD matrix elements are estimated from phenomenological potential models. We predict the differential $p_T$ spectra of various fully-charmed $S$-wave tetraquarks at the \texttt{LHC}, and compare with the results predicted from the fragmentation mechanism at large $p_T$ end.
1.Analyzing cancellation mechanism of the DM-quark scattering in a complex singlet extension of the Standard Model
Authors:Gi-Chol Cho, Chikako Idegawa
Abstract: We investigate a suppression mechanism of dark matter and quark scattering amplitudes in a complex singlet extension of the Standard Model. It has been pointed out that, in a some variant of the model, the scattering amplitudes cancel each other in the limit in which two mediator scalars degenerate in their masses. We study the origin of such the cancellation mechanism and show that the operators describing the Higgs-singlet scalar mixing play essential role. We derive sum rules for couplings in the general scalar potential of the model, which guarantee the cancellation of the scattering amplitudes in the tree and the 1-loop level.
2.Dai-Freed anomaly in the standard model and topological inflation
Authors:Masahiro Kawasaki, Tsutomu T. Yanagida
Abstract: When we impose the discrete symmetry in the standard model we have Dai-Freed global anomalies. However, interestingly if we introduce three right-handed neutrinos we can have an anomaly-free discrete $Z_4$ gauge symmetry. This $Z_4$ symmetry should be spontaneously broken down to the $Z_2$ symmetry to generate the heavy Majorana masses for the right-handed neutrinos. We show that this symmetry breaking naturally generates topological inflation, which is consistent with the CMB observations at present and predicts a significant tensor mode with scalar-tensor ratio $r > 0.03$. The right-handed neutrinos play an important role in reheating processes. The reheating temperature is as high as $\sim 10^8$GeV, and non-thermal leptogenesis successfully takes place.
3.Particles and antiparticles
Authors:Dezső Horváth, Zoltán Trócsányi
Abstract: We review the concept of chirality and charge for particles and antiparticles. We point out that the commonly accepted equivalence of particles and antiparticles - with difference only in the opposite signs of their charges, which follows from the CPT invariance - is valid only for free non-chiral particles. We show that with the weak interaction turned on the equivalence of particles and antiparticles is violated. We also discuss that within the Standard Model even free neutrinos are exceptions, they can be produced only in chiral states. We conclude that in spite of a long history of antiparticles, interesting theoretical and experimental challenges remain in their complete understanding.
4.Exploring the axion potential and axion walls in dense quark matter
Authors:Bonan Zhang, David E. A. Castillo, Ana G. Grunfeld, Marco Ruggieri
Abstract: We study the potential of the Quantum Chromodynamics axion in hot and/or dense quark matter, within a Nambu-Jona-Lasinio-like model that includes the coupling of the axion to quarks. Differently from previous studies, we implement local electrical neutrality and $\beta-$equilibrium, which are relevant for the description of the quark matter in the core of compact stellar objects. Firstly we compute the effects of the chiral crossover on the axion mass and self-coupling. We find that the low energy properties of axion are very sensitive to the phase transition of Quantum Chromodynamics, in particular, when the bulk quark matter is close to criticality. Then, for the first time in the literature we compute the axion potential at finite quark chemical potential and study the axion domain walls in bulk quark matter. We find that the energy barrier between two adjacent vacuum states decrease in the chirally restored phase: this results in a lower surface tension of the walls. Finally, we comment on the possibility of production of walls in dense quark matter.
5.The effects of the widths on the one loop electroweak corrections to the $pp \to WW$ process
Authors:N. Bekheddouma Abdi, R. Bouamrane, K. Khelifa-Kerfa
Abstract: In this paper, we probe the effects of the widths of the unstable particles on the one loop electroweak corrections for the $pp \to WW$ process at the TeV scale within the framework of the complex mass scheme. We also explore for this process the unitarity status at high energies.
6.Statement from the American Linear Collider Committee to the P5 subpanel
Authors:J. A. Bagger, S. Belomestnykh, P. C. Bhat, J. E. Brau, M. Demarteau, D. Denisov, P. D. Grannis, T. Junginger, A. J. Lankford, M. Liepe, T. W. Markiewicz, H. E. Montgomery, M. E. Peskin, J. Strube, A. P. White, G. W. Wilson
Abstract: This statement from the American Linear Collider Committee to the P5 subpanel has three purposes. It presents a brief summary of the case for an $e^+e^-$ Higgs factory that has emerged from Snowmass 2021. It highlights the special virtues of the ILC that are shared with other linear colliders but not with circular colliders. Finally, it calls attention to the resources available in the ILC White Paper for Snowmass (arXiv:2203.07622). The ALCC urges P5 to move the Higgs factory forward as a global project by assigning the idea of an $e^+e^-$ Higgs factory high priority, initiating a global discussion of the technology choice and cost sharing, and offering the option of siting the Higgs factory in the U.S.
7.Energy-momentum tensor in the scalar diquark model
Authors:Arturo Amor-Quiroz, William Focillon, Cédric Lorcé, Simone Rodini
Abstract: We compute all the gravitational form factors in the scalar diquark model at the one-loop level using two different regularization methods. We check explicitly that all the Poincar\'e sum rules are satisfied and we discuss in detail the results for the trace of the energy-momentum tensor. Finally we discuss the spatial distributions of energy and pressure in two and three dimensions.
8.Analytic Evolution of DGLAP Equations
Authors:Matthew Markovych, Asli Tandogan
Abstract: We present an analytical method to solve the leading order (LO) Dokshitzer-Gribov-Lipatov-Altarelli-Parisi (DGLAP) evolution equations, which describe how parton distribution functions (PDFs) vary through different energy scales. Our approach utilizes the analytical technique that was previously employed to address the evolution of singular distribution amplitudes. The method is straightforward, mathematically transparent, and requires very little computational power. The approach involves assuming that the PDF can be expanded into a series of terms, which follow a recursion relation that we derive. To demonstrate the efficacy of our method, we utilize a toy model of PDF at initial scale. We initiate with a reasonable approximation of the experimentally calculated PDF and demonstrate that our approach yields the asymptotic behavior of the PDF.
1.The decay $τ\to 3πν_τ$ and axial-vector meson $a_1$ in the NJL model
Authors:Volkov M. K., Nurlan K., Pivovarov A. A
Abstract: The branching fractions of $\tau \to \pi^+ \pi^-\pi^- \nu_\tau$ and $\tau \to \pi^- 2\pi^0\nu_\tau$ are calculated within the chiral NJL model. Features of the axial-vector $a_1$ meson which plays an important role in describing the $\tau$ decays are discussed. Permissible values for the mass and width of the $a_1$ meson are considered in accordance with the latest experiments.
2.Transverse momentum dependent shape function for $J/ψ$ production in SIDIS
Authors:Daniël Boer, Jelle Bor, Luca Maxia, Cristian Pisano, Feng Yuan
Abstract: It has been shown previously that the transverse momentum dependent (TMD) factorization of heavy quarkonium production requires a TMD shape function. Its perturbative tail can be extracted by matching the cross sections valid at low and high transverse momenta. In this article we compare the order-$\alpha_s$ TMD expressions with the order-$\alpha_s^2$ collinear ones for $J/\psi$ production in semi-inclusive deep inelastic scattering (SIDIS), employing nonrelativistic QCD in both cases. In contrast to previous studies, we find that the small transverse momentum limit of the collinear expressions contain discontinuities. We demonstrate how to properly deal with them and include their finite contributions to the TMD shape functions. Moreover, we show that soft gluon emission from the low transverse momentum Born diagrams provide the same leading order TMD shape functions as required for the matching. Their revised perturbative tails have a less divergent behaviour as compared to the TMD fragmentation functions of light hadrons. Finally, we investigate the universality of TMD shape functions in heavy quarkonium production, identify the need for process dependent factorization and discuss the phenomenological implications.
3.Resonant and polarization effects in the processes of quantum electrodynamics in a strong magnetic field
Authors:R. I. Kholodov, O. P. Novak, M. M. Diachenko
Abstract: The monograph considers resonance and polarization effects in quantum electrodynamics processes that take place in a strong external magnetic field. A method for analyzing spin-polarization effects has been developed. The factorization of process cross sections in resonant conditions and the representation of these cross sections in the form of Breit-Wigner are considered. The possibility of testing these effects in modern international projects to test quantum electrodynamics in strong fields is shown.
4.Khuri-Treiman analysis of $J/ψ\toπ^{+}π^{-}π^{0}$
Authors:JPAC Collaboration, M. Albaladejo, S. Gonzàlez-Solís, Ł. Bibrzycki, C. Fernández-Ramírez, N. Hammoud, V. Mathieu, M. Mikhasenko, G. Montaña, R. J. Perry, A. Pilloni, A. Rodas, W. A. Smith, A. Szczepaniak, D. Winney
Abstract: We study the decay $J/\psi\to\pi^{+}\pi^{-}\pi^{0}$ within the framework of the Khuri-Treiman equations. We find that the BESIII experimental di-pion mass distribution in the $\rho(770)$-region is well reproduced with a once-subtracted $P$-wave amplitude. Furthermore, we show that $F$-wave contributions to the amplitude improve the description of the data in the $\pi\pi$ mass region around 1.5 GeV. We also present predictions for the $J/\psi\to\pi^{0}\gamma^{*}$ transition form factor.
5.Light-quark Yukawa couplings from off-shell Higgs production
Authors:Elisa Balzani, Ramona Gröber, Marco Vitti
Abstract: Yukawa couplings of the first quark generation are notoriously difficult to constrain due to their small values within the Standard Model. Here we propose Higgs off-shell production, with the Higgs boson decaying to four leptons, as a probe of the up- and down-quark Yukawa couplings. Using kinematic discriminants similar to the ones employed in the Higgs width measurements we find that the down (up) Yukawa coupling can be constrained to a factor of 156 (260) times its Standard Model value at the high-luminosity LHC assuming only experimental systematic uncertainties. Off-shell Higgs production hence provides better sensitivity to the first-generation quark Yukawa couplings with respect to other probes such as Higgs+jet or Higgs pair production.
6.Transvese momentum dependent parton distributions of pion at leading twist
Authors:Wei Kou, Chao Shi, Xurong Chen, Wenbao Jia
Abstract: We calculate the leading twist pion unpolarized transverse momentum distribution $f_1(x,k_T^2)$ and the Boer-Mulders function $h_1^\perp(x,k_T^2)$, using leading Fock-state light front wave functions (LF-LFWFs) based on Dyson-Schwinger and Bethe-Salpeter equations. These DS-BSEs based LF-LFWFs provide dynamically generated s- and p-wave components, which are indispensable in producing chirally odd Boer-Mulders function that has one parton spin flipped. Employing a non-perturbative SU(3) gluon rescattering kernel to treat the gauge link of the Boer-Mulders function, we thus obtain both TMDs at hadronic scale and then evolve them to the scale of $\mu^2=4.0$ GeV$^2$. We finally calculate the generalized Boer-Mulders shift and find it to be in agreement with the lattice prediction.
7.Energy loss of heavy quarks in the presence of magnetic field
Authors:Mohammad Yousuf Jamal, Jai Prakash, Indrani Nilima, Aritra Bandyopadhyay
Abstract: We aim to study the energy loss of heavy quarks in the presence of the background magnetic field. To do so, we first investigate the effect of medium polarization on the propagation of charm and a bottom quark, considering an equilibrating quark-gluon plasma created in the relativistic heavy-ion colliders such as RHIC and LHC. The analysis is performed considering the high magnetic field produced due to the spectators from the initial hard collisions. Furthermore, we studied the nuclear modification factor, $R_{AA},$ for different values of magnetic field for the parameters relevant at RHIC and LHC energies. The energy loss of heavy quarks (HQs) was found to increase significantly. The corresponding nuclear modification factor ($R_{AA}$) suppresses upto 15\% at the highest magnetic field strength studied ($eB$ = 0.6 $\text{GeV}^2$).
1.Type-II see-saw at $μ^+$$μ^-$ collider
Authors:Siddharth P. Maharathy, Manimala Mitra
Abstract: Doubly-charged Higgs bosons have extensively been searched at the LHC. In this work, we study the sensitivity reach of the doubly-charged scalar ($H^{\pm\pm}$) in muon collider for the well-known Type-II seesaw scenario. First, we perform a cut-based analysis to predict the discovery prospect in the muon collider operating with 3 TeV center of mass energy. In addition to this, we have also performed a multivariate analysis and compare the cut-based result with the result obtained from the multivariate analysis. We find that the cut-based analysis is more significant as compared to the multivariate analysis in the large doubly-charged scalar mass region. We predict that a doubly-charged scalar mass, $M_{H^{\pm\pm}}$, upto 1450 GeV can be probed with $5\sigma$ significance for center of mass $\sqrt{s}= 3$ TeV and integrated luminosity $\mathcal{L} = 1000\,\textrm{fb}^{-1}$.
2.Probing vortical structures in heavy-ion collisions at RHIC-BES energies through helicity polarization
Authors:Cong Yi, Xiang-Yu Wu, Di-Lun Yang, Jian-Hua Gao, Shi Pu, Guang-You Qin
Abstract: We investigate the hydrodynamic helicity polarization of $\Lambda$ hyperons, defined as the projection of the spin polarization vector along the directions of particle momenta, at RHIC-BES energies by utilizing the relativistic (3+1)D CLVisc hydrodynamics framework with SMASH initial conditions. As opposed to local spin polarization at high energy collisions, our hydrodynamic simulations demonstrate that the helicity polarization induced by the kinetic vorticity dominates over other contributions at intermediate and low collision energies. Our findings provide an opportunity to probe the fine structure of local kinetic vorticity as a function of azimuthal angle at intermediate and low collision energies by mapping our predictions to the future measurements in experiments.
3.The pion-kaon scattering amplitude and the $K^0(700)$ and $K^*(892)$ resonances at finite temperature
Authors:Angel Gómez Nicola, Jacobo Ruiz de Elvira, Andrea Vioque-Rodríguez
Abstract: We perform a complete calculation of the pion-kaon scattering amplitude in Chiral Perturbation Theory at finite temperature, paying particular attention to the analytic structure of the amplitude and the main differences with respect to the zero temperature case. We also extend the Inverse Amplitude Method at finite temperature for unequal-mass scattering processes, which allows us to unitarize the amplitude and obtain the thermal evolution of the $K_0^*(700)$ and $K^*(892)$ pole parameters. As a direct application of our analysis, we show that the thermal evolution of the $K_0^*(700)$ resonance is crucial to explain the behavior of the scalar susceptibility for isospin $I=1/2$, which in turn, is directly connected with chiral and $U(1)_A$ restoration properties of the QCD phase diagram.
4.Constraining the equation of state with heavy quarks in the quasi-particle model of QCD matter
Authors:Feng-Lei Liu, Xiang-Yu Wu, Shanshan Cao, Guang-You Qin, Xin-Nian Wang
Abstract: In a quasi-particle model of QCD matter at finite temperature with thermal masses for quarks and gluons from hard thermal loops, the equation of state (EOS) can be described by an effective temperature dependence of the strong coupling $g(T)$. Assuming the same effective coupling between the exchanged gluon and thermal partons, the EOS can also be related to parton energy loss.} Based on the quasi-particle linear Boltzmann transport (QLBT) model coupled to a (3+1)-dimensional viscous hydrodynamic model of the quark-gluon plasma (QGP) evolution and a hybrid fragmentation-coalescence model for heavy quark hadronization, we perform a Bayesian analysis of the experimental data on $D$ meson suppression $R_{\rm AA}$ and anisotropy $v_2$ at RHIC and the LHC. We achieve a simultaneous constraint on the QGP EOS and the heavy quark transport coefficient, both consistent with the lattice QCD results.
5.LIGO-VIRGO constraints on dark matter and leptogenesis triggered by a first order phase transition at high scale
Authors:Debasish Borah, Arnab Dasgupta, Indrajit Saha
Abstract: We study the possibility of constraining a scenario with high scale first order phase transition (FOPT) responsible for the cogenesis of baryon and dark matter using gravitational wave (GW) (non)-observations. While the FOPT at high scale is responsible for generating baryon asymmetry through leptogenesis and dark matter via the \textit{mass-gain} mechanism, the resulting GW spectrum falls within the ongoing LIGO-VIRGO experimental sensitivity. The dark matter is preferred to be in the non-thermal ballpark with sub-GeV masses and the criteria of successful dark matter relic rules out a large portion of the parameter space consistent with high scale FOPT and successful leptogenesis. Some part of the parameter space allowed from dark matter and leptogenesis criteria also gives rise to a large signal-to-noise ratio at ongoing experiments and hence can be disfavoured in a conservative way from the non-observation of such stochastic GW background. Future data from ongoing and planned experiments will offer a complementary and indirect probe of the remaining parameter space which is typically outside the reach of any direct experimental probe.
6.How robust are particle physics predictions in asymptotic safety?
Authors:Wojciech Kotlarski, Kamila Kowalska, Daniele Rizzo, Enrico Maria Sessolo
Abstract: The framework of trans-Planckian asymptotic safety has been shown to generate phenomenological predictions in the Standard Model and in some of its simple new physics extensions. A heuristic approach is often adopted, which bypasses the functional renormalization group by relying on a parametric description of quantum gravity with universal coefficients that are eventually obtained from low-energy observations. Within this approach, a few simplifying approximations are typically introduced, including the computation of matter renormalization group equations at 1~loop, an arbitrary definition of the position of the Planck scale at $10^{19}$ GeV, and an instantaneous decoupling of gravitational interactions below the Planck scale. In this work we systematically investigate, both analytically and numerically, the impact of dropping each of those approximations on the predictions for certain particle physics scenarios. In particular we study two extensions of the Standard Model, the gauged $B-L$ model and the leptoquark $S_3$ model, for which we determine a set of irrelevant gauge and Yukawa couplings. In each model, we present numerical and analytical estimates of the uncertainties associated with the predictions from asymptotic safety.
7.The heavy quark expansion for lifetimes: Towards the QCD corrections to power suppressed terms
Authors:Thomas Mannel, Daniel Moreno, Alexei A. Pivovarov
Abstract: We consider the Heavy Quark Expansion (HQE) for the nonleptonic decay rates of heavy hadrons, and compute the NLO QCD corrections to power terms up to order $1/m_Q^2$. We neglect the masses of the final-state quarks, so the application of our result is mainly for charmed hadrons. Our result can be applied also to bottomed hadrons as they constitute the main effect to this order up to corrections of $\mathcal{O}(m_c/m_b)$ and contributions due to penguin operators. We discuss the impact of our result for the lifetimes of heavy hadrons.
8.Light-cone distribution amplitudes of a light baryon in large-momentum effective theory
Authors:Zhi-Fu Deng, Chao Han, Wei Wang, Jun Zeng, Jia-Lu Zhang
Abstract: Momentum distributions of quarks/gluons inside a light baryon in a hard exclusive process are encoded in the light-cone distribution amplitudes (LCDAs). In this work, we point out that the leading twist LCDAs of a light baryon can be obtained through a simulation of a quasi-distribution amplitude calculable on lattice QCD within the framework of the large-momentum effective theory. We calculate the one-loop perturbative contributions to LCDA and quasi-distribution amplitudes and explicitly demonstrate the factorization of quasi-distribution amplitudes at the one-loop level. Based on the perturbative results, we derive the matching kernel in the $\overline{\rm MS}$ scheme and regularization-invariant momentum-subtraction scheme. Our result provides a first step to obtaining the LCDA from first principle lattice QCD calculations in the future.
9.First computation of Mueller Tang processes using the full NLL BFKL approach
Authors:Dimitri Colferai, Federico Deganutti, Timothy G Raben, Christophe Royon
Abstract: We present the full next-to-leading order (NLO) prediction for the jet-gap-jet cross section at the LHC within the BFKL approach. We implement, for the first time, the NLO impact factors in the calculation of the cross section. We provide results for differential cross sections as a function of the difference in rapidity and azimuthal angle betwen the two jets and the second leading jet transverse momentum. The NLO corrections of the impact factors induce an overall reduction of the cross section with respect to the corresponding predictions with only LO impact factors. We note that NLO impact factors feature a logarithmic dependence of the cross section on the total center of mass energy which formally violates BFKL factorization. We show that such term is one order of magnitude smaller than the total contribution, and thus can be safely included in the current prediction without a need of further resummation of such logarithmic terms. Fixing the renormalization scale $\mu_R$ according to the principle of minimal sensitivity, suggests $\mu_R$ about 4 times the sum of the transverse jet energies and provides smaller theroretical uncertainties with respect to the leading order case.
10.Anomalies, $η$ , $η$' as keys to glueballs
Authors:Jean-Marie Frère
Abstract: Glueballs are the most straightforward prediction of QCD, yet while they have likely been produced, none has been unequivocally identified. We pursue a backdoor approach through anomalies, and singularly the $\eta$ and $\eta$' which brings light to this irritating situation. In particular, we advocate to consider the full decay chain $J/\psi \rightarrow X \gamma , X \rightarrow \eta \eta'$ (into glue-rich states followed by glue-rich decays). We also suggest new BES III searches, namely for the $\pi_1$ into $\eta(') \pi^0$, (this would be the partner of their recently observed $\eta_1(1855)$). Another useful investigation would be for other channels (or semi-inclusive) $f_0 (1500)$ decays (see last section)
1.Constraints on NJL four-fermion effective interactions from neutrinoless double beta decay
Authors:Luca Pacioselli Dipartimento di Fisica e Geologia, Università degli Studi di Perugia INFN Sezione di Perugia, Orlando Panella INFN Sezione di Perugia, Matteo Presilla INFN Sezione di Perugia, She-Sheng Xue INFN Sezione di Perugia ICRANet, Pescara Dipartimento di Fisica, Sapienza-Università di Roma ICTP-AP, University of Chinese Academy of Sciences, Beijing, China
Abstract: We study the contribution of a heavy right-handed Majorana neutrino to neutrinoless double beta decay ($0\nu\beta\beta$) via four-fermion effective interactions of Nambu-Jona-Lasinio (NJL) type. In this physical scenario, the sterile neutrino contributes to the nuclear transition through gauge, contact, and mixed interactions. Using the lower limit on the half-life of $0\nu\beta\beta$ from the KamLAND-Zen experiment, we then constrain the effective right-handed coupling between the sterile neutrino and the $W$ boson: $\mathcal{G}^{W}_{R}$. Eventually, we show that the obtained bounds are compatible with those found in the literature, which highlights the complementarity of this type of phenomenological study with high-energy experiments.
2.Environmentally aware displaced vertices
Authors:Spyros Argyropoulos, Clare Burrage, Christoph Englert
Abstract: Dynamical theories of dark energy predict new degrees of freedom with particular environmental sensitivity to avoid constraints on fifth forces. We show that the similar, yet complementary multi-purpose detector setup of the ATLAS and CMS experiments provides a unique opportunity to place sensitivity on such scenarios in a narrow, yet relevant parameter range. Furthermore, our investigation gives rise to a novel phenomenological signature that the LHC experiments can pursue to exploit their complementary detector design from a BSM perspective.
3.Pileup density estimate independent on jet multiplicity
Authors:Peter Berta, Juraj Smieško, Martin Spousta
Abstract: The hard-scatter processes in hadronic collisions are often largely contaminated with soft background coming from pileup in proton-proton collisions, or underlying event in heavy-ion collisions. There are multiple methods to remove the effect of pileup for jets. Two such methods, Area Subtraction and Constituent Subtraction, use the pileup density as the main ingredient to estimate the magnitude of pileup contribution on an event-by-event basis. The state-of-the-art approaches to estimating pileup density are sensitive to the number of hard-scatter jets in the event. This paper presents a new pileup-density estimation method that minimizes the sensitivity on the presence of hard-scatter jets in the event. Using a detector-level simulation, we provide a comparison of the new method with the state-of-the-art estimation methods. We observe a significantly lower bias for the estimated pileup density when using the new method. We conclude that the new method has the potential to significantly improve pileup mitigation in proton-proton collisions or the underlying event subtraction in heavy-ion collisions.
4.Charmed hadron lifetimes
Authors:James Gratrex, Blaženka Melić, Ivan Nišandžić
Abstract: We provide updated predictions of the lifetimes of singly charmed baryons and mesons within the heavy quark expansion, with all known corrections included. A special attention is devoted to the choice of the charm mass and wavefunctions of heavy baryons. Our results accommodate the experimentally-favoured hierarchy of singly charmed baryon lifetimes \begin{eqnarray*} \tau(\Xi_c^0) < \tau(\Lambda_c^+)< \tau(\Omega_c^0) < \tau(\Xi_c^+)\, \end{eqnarray*} in contrast to earlier theoretical findings. Predictions for charmed meson lifetimes and semileptonic branching ratios are also in agreement, within uncertainties, with a recent comprehensive study and with experimental results.
5.Low Seesaw Scale Solution for $M_W$ and $(g-2)_μ$
Authors:A. de Giorgi, L. Merlo, S. Pokorski
Abstract: In this short talk, we present a renormalizable model that can i) generate neutrino masses via a low-scale seesaw mechanism and ii) solve the long-standing $(g-2)_\mu$ and the more recent CDF II $M_W$-anomalies. This is minimally achieved by introducing two sterile neutrinos and a single electroweak-doublet vector-like lepton, with masses $< 2$ TeV. We focus on the one-generation scenario and the requirements to extend it to three generations.
6.Big Bang initial conditions and self-interacting hidden dark matter
Authors:Jinzheng Li, Pran Nath
Abstract: A variety of supergravity and string models involve hidden sectors where the hidden sectors may couple feebly with the visible sectors via a variety of portals. While the coupling of the hidden sector to the visible sector is feeble its coupling to the inflaton is largely unknown. It could couple feebly or with the same strength as the visible sector which would result in either a cold or a hot hidden sector at the end of reheating. These two possibilities could lead to significantly different outcomes for observables. We investigate the thermal evolution of the two sectors in a cosmologically consistent hidden sector dark matter model where the hidden sector and the visible sector are thermally coupled and their thermal evolution occurs without the assumption of separate entropy conservation for each sector. Within this framework we analyze several phenomena to illustrate their dependence on the initial conditions. These include the allowed parameter space of models, dark matter relic density, proton-dark matter cross section, effective massless neutrino species at BBN time, self-interacting dark matter cross-section, where self-interaction occurs via exchange of dark photon, and Sommerfeld enhancement. Finally fits to the velocity dependence of dark matter cross sections from galaxy scales to the scale of galaxy clusters is given. The analysis indicates significant effects of the initial conditions on the observables listed above. The analysis is carried out within the framework where dark matter is constituted of dark fermions and the mediation between the visible and the hidden sector occurs via the exchange of dark photons. The techniques discussed here may have applications for a wider class of hidden sector models using different mediations between the visible and the hidden sectors to explore the impact of Big Bang initial conditions on observable physics.
1.Evolution of structure functions in momentum space
Authors:Tuomas Lappi, Heikki Mäntysaari, Hannu Paukkunen, Mirja Tevio
Abstract: We formulate the momentum-space Dokshitzer-Gribov-Lipatov-Altarelli-Parisi (DGLAP) evolution equations for structure functions measurable in deeply inelastic scattering. We construct a six-dimensional basis of structure functions that allows for a full three flavor structure and thereby provides a way to calculate perturbative predictions for physical cross sections directly without unobservable parton distribution functions (PDFs) and without the associated scheme dependence. We derive the DGLAP equations to first non-zero order in strong coupling $\alpha_s$, but the approach can be pursued to arbitrary order in perturbation theory. We also numerically check our equations against the conventional PDF formulation.
2.A new look at $ψ(4160)$ and $ψ(4230)$
Authors:Zhi-Yong Zhou, Chun-Yong Li, Zhiguang Xiao
Abstract: By simultaneously analyzing the cross section data of $e^+e^-\rightarrow D\bar D, D\bar D^*, D^*\bar D^*, D\bar D\pi$ in a coupled-channel scheme with unitarity, we found that, in contrast to the conventional wisdom, the pole of $\psi(2^3D_1)$ might be located at about $\sqrt{s}=4222-32i\mathrm{MeV}$. This observation implies a possibility that the two resonances, dubbed the $\psi(4160)$ and $\psi(4230)$ in the PDG table now, might be the same $\psi(2^3D_1)$ state. Such a suggestion could provide more insight to our understanding the enigmatic decay properties of $\psi(4160)$ and $\psi(4230)$. Furthermore, this coupled-channel scheme could be applied to study other phenomena with several interfering resonances.
3.Dark matter induced dynamical symmetry breaking
Authors:Kristjan Kannike
Abstract: We consider the classically scale invariant Higgs-dilaton model of dynamical symmetry breaking extended with an extra scalar field that plays the role of dark matter. The Higgs boson is light near a critical boundary between different symmetry breaking phases, where quantum corrections beyond the usual Gildener-Weinberg approximation become relevant. The only large scale, which generates the other scales, is given by the mass of dark matter. This implies a tighter connection between dark matter and Higgs phenomenology. The model has only three free parameters, yet it allows for the observed relic abundance of dark matter while respecting all constraints. The direct detection cross section mediated by the Higgs boson is determined by the dark matter mass alone and is testable at future experiments.
4.Effective Field Theories for Dark Matter Pairs in the Early Universe
Authors:Simone Biondini, Nora Brambilla, Gramos Qerimi, Antonio Vairo
Abstract: In this conference paper, we consider effective field theories of non-relativistic dark matter particles interacting with a light force mediator in the early expanding universe. We present a general framework, where to account in a systematic way for the relevant processes that may affect the dynamics during thermal freeze-out. In the temperature regime where near-threshold effects, most notably the formation of bound states and Sommerfeld enhancement, have a large impact on the dark matter relic density, we scrutinize possible contributions from higher excited states and radiative corrections in the annihilations and decays of dark-matter pairs.
5.Jet substructure observables for jet quenching in Quark Gluon Plasma: a Machine Learning driven analysis
Authors:Miguel Crispim Romão, José Guilherme Milhano, Marco van Leeuwen
Abstract: We present a survey of a comprehensive set of jet substructure observables commonly used to study the modifications of jets resulting from interactions with the Quark Gluon Plasma in Heavy Ion Collisions. The \jewel{} event generator is used to produce simulated samples of quenched and unquenched jets. Three distinct analyses using Machine Learning techniques on the jet substructure observables have been performed to identify both linear and non-linear relations between the observables, and to distinguish the Quenched and Unquenched jet samples. We find that most of the observables are highly correlated, and that their information content can be captured by a small set of observables. We also find that the correlations between observables are robust to quenching effects and that specific pairs of observables exhaust the full sensitivity to quenching effects. The code, the datasets, and instructions on how to reproduce this work are also provided.
6.Late baryogenesis in a two-brane universe with a latent CP violation
Authors:Michael Sarrazin, Coraline Stasser
Abstract: We introduce a toy model of baryogenesis where our usual visible Universe is a 3-brane coevolving with a hidden 3-brane in a multidimensional bulk, in an ekpyrotic-like approach. The visible matter and antimatter sectors are coupled with the hidden matter and antimatter sectors, breaking the CP invariance and leading to baryogenesis occurring after the quark-gluon era. The issue of leptogenesis is also discussed. This model complements cosmological approaches in which dark matter and dark energy could naturally emerge from many-brane scenarios.
7.A Realistic Neutrino mixing scheme arising from $A_4$ symmetry
Authors:Manash Dey, Subhankar Roy
Abstract: We propose a unique lepton mixing mixing matrix and how it can be associated with a specific neutrino mass matrix texture is studied. The work highlights that mixing pattern in its exact form can be achieved in the framework of hybrid seesaw mechanism in association with $A_4$ discrete flavour symmetry.
1.Testing electroweak scale seesaw models at $e^{-} γ$ and $γ γ$ colliders
Authors:Arindam Das, Sanjoy Mandal, Sujay Shil
Abstract: We investigate the possibilities of probing the electroweak scale seesaw scenarios such as type-I, type-II and type-III seesaw at $e^-\gamma$ and $\gamma\gamma$ colliders. For the case of type-I seesaw, the heavy neutrinos can be produced at $e^{-}\gamma$ colliders in association with a $W$ boson. We study a variety of final states in this case including single and multilepton modes in association with jets to estimate bounds on the light-heavy neutrino mixing angle. In case of type-II seesaw, doubly charged multiplets of the SU$(2)_L$ triplet scalar can be produced in pair at $\gamma \gamma$ collider. We study the multi-leptonic decay modes coming from this pair production of doubly charged Higgs and show how one can probe neutrino mass hierarchy. We also study same sign $W$ boson production from the doubly charged Higgs to study multilepton modes in association with missing energy. From the type-III seesaw, we study same sign dilepton+jets and trilepton+jets modes at $e^-\gamma$ collider which are coming from the neutral and charged component of the triplet fermion in association with a $W$ boson and $Z$ boson, respectively. Due to the existing limits on the triplet fermions from the LHC we choose heavier mass so that the gauge boson originated from the decay of a neutral multiplet can be sufficiently boosted producing a fat-jet signature in association with same sign dilepton and trilepton. Finally we estimate bounds on the light neutrino-heavy triplet fermion mixing angle and compare with the existing bounds.
2.Bayesian inference of momentum and length dependence of jet energy loss
Authors:Jordan Wu, Weiyao Ke, Xin-Nian Wang
Abstract: Using a simple model for medium modification of the jet function through a parameterized form of the jet energy loss distribution, we carry out a comprehensive Bayesian analysis of the world data on single inclusive jet spectra in heavy-ion collisions at both RHIC and LHC energies. We extract the average jet energy loss $\langle \Delta E\rangle$ as a function of jet transverse momentum $p_T$ for each collision system and centrality independently. Assuming jet energy loss is proportional to the initial parton density $\rho \sim dN_{\rm ch}/d\eta/\pi R_{\rm eff}^2$ as estimated from the pseudorapidity density of charged hadron multiplicity $dN_{\rm ch}/d\eta$ and the effective system size $R_{\rm eff}\sim N_{\rm part}^{1/3}$ given by the number of participant nucleons $N_{\rm part}$, the scaled average jet energy loss $\langle \Delta E\rangle/\rho \sim R_{\rm eff}^{0.59} p_T^{0.13}\ln p_T $ for jet cone-size $R=0.4$ is found to have a momentum dependence that is slightly stronger than a logarithmic form while the system size or length dependence is slower than a linear one. The fluctuation of jet energy loss is, however, independent of the initial parton density or the system size. These are consistent with results from Monte Carlo simulations of jet transport in a fast expanding quark-gluon plasma in high-energy heavy-ion collisions.
3.Kinematical higher-twist corrections in $γ^* \to M \bar M γ$. I. Neutral meson production
Authors:Bernard Pire, Qin-Tao Song
Abstract: We carry out the calculation of kinematical higher-twist corrections to the cross section of $\gamma^* \to M \bar{M} \gamma$ up to twist 4, where $M$ is a scalar or pseudoscalar neutral meson. The three independant helicity amplitudes are presented in terms of the twist-2 generalized distribution amplitudes (GDAs), which are important non-perturbative quantities for understanding the 3D structure of hadrons. Since this process can be measured by BESIII in $e^+ e^-$ collisions, we also perform the numerical estimate of the kinematical higher-twist corrections by using the kinematics of BESIII. We adopt the $\pi \pi$ GDA extracted from Belle measurements and the asymptotic $\pi \pi$ GDA to study the size of the kinematical corrections in the case of pion meson pair, and a model $\eta \eta$ GDA is used to see the impact of target mass corrections $\mathcal O(m^2/s)$ for $\gamma^* \to \eta \eta \gamma$. Our results show that the kinematical higher-twist corrections account for $\sim 20\%$ of the cross sections at BESIII on the average, and it is necessary to include them if one tries to extract GDAs from experimental measurements precisely. Furthermore, the energy-momentum tensor (EMT) form factors can be obtained for mesons with the help of their GDAs, from which one can investigate interesting quantities such as the meson mass radius and mass distribution.
4.Anisotropic flow and the valence quark skeleton of hadrons
Authors:Meijian Li, Wenyang Qian, Bin Wu, Hong Zhang
Abstract: We study transverse momentum anisotropies, in particular, the elliptic flow $v_2$ due to the interference effect sourced by valence quarks in high-energy hadron-hadron collisions. Our main formula is derived as the high-energy (eikonal) limit of the impact-parameter dependent cross section in quantum field theory, which agrees with that in terms of the impact parameter in the classical picture. As a quantitative assessment of the interference effect, we calculate $v_2$ in the azimuthal distribution of gluons at a comprehensive coverage of the impact parameter and the transverse momentum in high-energy pion-pion collisions. In a broad range of the impact parameter, a sizable amount of $v_2$, comparable with that produced due to saturated dense gluons or final-state interactions, is found to develop. In our calculations, the valence sector of the pion wave function is obtained numerically from the Basis Light-Front Quantization, a non-perturbative light-front Hamiltonian approach. And our formalism is generic and can be applied to other small collision systems like proton-proton collisions.
5.Constraining low-scale dark phase transitions with cosmological observations
Authors:Shihao Deng, Ligong Bian
Abstract: We investigate the effects of the low-scale cosmological first-order phase transitions on the neutrino decoupling and constrain the PT parameters with the cosmological observations of big bang nucleosynthesis and cosmic microwave background. We consider the phase transitions that occur at the MeV-scale which can produce stochastic gravitational wave background to be probed by pulsar timing array experiments. We find that the phase transition can modify the effective number of neutrinos and the primordial nucleosynthesis. In turn, the cosmological observations can exclude slow and strong phase transitions around the MeV scale.
6.Chiral magnetohydrodynamics with zero total chirality
Authors:Axel Brandenburg, Kohei Kamada, Kyohei Mukaida, Kai Schmitz, Jennifer Schober
Abstract: We study the evolution of magnetic fields coupled with chiral fermion asymmetry in the framework of chiral magnetohydrodynamics with zero initial total chirality. The initial magnetic field has a turbulent spectrum peaking at a certain characteristic scale and is fully helical with positive helicity. The initial chiral chemical potential is spatially uniform and negative. We consider two opposite cases where the ratio of the length scale of the chiral plasma instability (CPI) to the characteristic scale of the turbulence is smaller and larger than unity. These initial conditions might be realized in cosmological models such as certain types of axion inflation. The magnetic field and chiral chemical potential evolve with inverse cascading in such a way that the magnetic helicity and chirality cancel each other at all times. The CPI time scale is found to determine mainly the time when the magnetic helicity spectrum attains negative values at high wave numbers. The turnover time of the energy-carrying eddies, on the other hand, determines the time when the peak of the spectrum starts to shift to smaller wave numbers via an inverse cascade. The onset of helicity decay is determined by the time when the chiral magnetic effect becomes efficient at the peak of the initial magnetic energy spectrum. When spin flipping is important, the chiral chemical potential vanishes and the magnetic helicity becomes constant, which leads to a faster increase of the correlation length, as expected from magnetic helicity conservation. This also happens when the initial total chirality is imbalanced. Our findings have important implications for baryogenesis after axion inflation.
7.Dimension-8 SMEFT Analysis of Minimal Scalar Field Extensions of the Standard Model
Authors:John Ellis, Ken Mimasu, Francesca Zampedri
Abstract: We analyze the constraints obtainable from present data using the Standard Model Effective Field Theory (SMEFT) on extensions of the Standard Model with additional electroweak singlet or triplet scalar fields. We compare results obtained using only contributions that are linear in dimension-6 operator coefficients with those obtained including terms quadratic in these coefficients as well as contributions that are linear in dimension-8 operator coefficients. We also implement theoretical constraints arising from the stability of the electroweak vacuum and perturbative unitarity. Analyzing the models at the dimension-8 level constrains scalar couplings that are not bounded at the dimension-6 level. The strongest experimental constraints on the singlet model are provided by Higgs coupling measurements, whereas electroweak precision observables provide the strongest constraints on the triplet model. In the singlet model the present di-Higgs constraints already play a significant role. We find that the current constraints on model parameters are already competitive with those anticipated from future di- and tri-Higgs measurements. We compare our results with calculations in the full model, exhibiting the improvements when higher-order SMEFT terms are included. We also identify regions in parameter space where the SMEFT approximation appears to break down. We find that the combination of current constraints with the theoretical bounds still admits regions where the SMEFT approach is not valid, particularly for lower scalar boson masses.
8.Isolated photon production in association with a jet pair through next-to-next-to-leading order in QCD
Authors:Simon Badger, Michal Czakon, Heribertus Bayu Hartanto, Ryan Moodie, Tiziano Peraro, Rene Poncelet, Simone Zoia
Abstract: In this work, we provide a comprehensive set of differential cross-section distributions for photon + di-jet production in proton-proton collisions with next-to-next-to-leading order precision in massless QCD. The event selection corresponds to recent measurements by the ATLAS collaboration. We observe an improved description of data in comparison to lower-order calculations in the case of observables that are expected to be well described by perturbation theory. The results also show better agreement with data than parton-shower-matched and multi-jet-merged predictions generated for the ATLAS analysis using the \textsc{Sherpa} Monte Carlo. A particular highlight of our study is the use of exact five-point two-loop virtual amplitudes. This is the first calculation of a complete two-to-three hadron-collider process at next-to-next-to-leading order in QCD that does not rely on the leading-colour approximation at two loops. We demonstrate, nevertheless, that the sub-leading-colour effects present in the infrared- and ultraviolet-finite double-virtual contributions are negligible in view of the remaining scale uncertainties.
1.Revisiting Affleck-Dine Leptogenesis with light sleptons
Authors:Kazuki Enomoto, Koichi Hamaguchi, Kohei Kamada, Juntaro Wada
Abstract: We revisit the Affleck-Dine leptogenesis via the $L H_u$ flat direction with a light slepton field. Although the light slepton field is favored in low-energy SUSY phenomenologies, such as the muon $g-2$ anomaly and bino-slepton coannihilation, it may cause a problem in the Affleck-Dine leptogenesis: it may create an unwanted charge-breaking vacuum in the Affleck-Dine field potential so that the Affleck-Dine field is trapped during the course of leptogenesis. We investigate the conditions under which such an unwanted vacuum exists and clarify that both thermal and quantum corrections are important for the (temporal) disappearance of the charge-breaking minimum. We also confirm that if the charge-breaking vacuum disappears due to the thermal or quantum correction, the correct baryon asymmetry can be produced while avoiding the cosmological gravitino problem.
2.Rare Leptonic Processes Induced by Massless Dark Photon
Authors:Xiaolong Deng, Florentin Jaffredo, Minoru Tanaka
Abstract: We introduce a dark photon considering a U(1) gauge extension of the standard model in particle physics. Provided that the extra U(1) symmetry is unbroken, the dark photon is massless and has no coupling to the standard electromagnetic current. Higher-dimensional operators describe interactions of the massless dark photon with particles in the standard model. We investigate the interactions of the massless dark photon with charged leptons via dipole operators, mainly focusing on the lepton family-violating processes. We present an improved constraint in the polarized two-body muon decay and a set of new bounds in tau decays. We also examine possible lepton family-violating signals of the massless dark photon in future lepton colliders.
3.Grand Gauge-Higgs Unification on $T^2/{\mathbb Z}_3$ via Diagonal Embedding Method
Authors:Kentaro Kojima, Kazunori Takenaga, Toshifumi Yamashita
Abstract: We study a novel six-dimensional gauge theory compactified on the $T^2/{\mathbb Z}_3$ orbifold utilizing the diagonal embedding method. The bulk gauge group is $G\times G\times G$, and the diagonal part $G^{\rm diag}$ remains manifest in the effective four-dimensional theory. Further spontaneous breaking of the gauge symmetry occurs through the dynamics of the zero modes of the extra-dimensional components of the gauge field. We apply this setup to the $SU(5)$ grand unified theory and examine the vacuum structure determined by the dynamics of the zero modes. The phenomenologically viable models are shown, in which the unified symmetry $G^{\rm diag}\cong SU(5)$ is spontaneously broken down to $SU(3)\times SU(2)\times U(1)$ at the global minima of the one-loop effective potential for the zero modes. This spontaneous breaking provides notable features such as a realization of the doublet-triplet splitting without fine tuning and a prediction of light adjoint fields.
4.Assisted neutrino pair production in combined external fields
Authors:Naser Ahmadiniaz, Rashid Shaisultanov, Ralf Schützhold
Abstract: Neutrino--antineutrino ($\nu\bar\nu$) pair production is one of the main processes responsible for the energy loss of stars. Apart from the collision of two ($\gamma\gamma\to\nu\bar\nu$) or three ($\gamma\gamma\gamma\to\nu\bar\nu$) real photons, photon decay and photon collisions in the presence of nuclear Coulomb fields or external magnetic fields have been considered previously. Here, we study the low-energy photon decay into a pair of neutrino and antineutrino in the presence of a combined homogeneous magnetic field and the Coulomb field of a nucleus with charge number $Z$.
5.Accessing the gluon GTMD $\boldsymbol{F_{1,4}}$ in exclusive $\boldsymbol{π^0}$ production in $\boldsymbol{ep}$ collisions
Authors:Shohini Bhattacharya, Duxin Zheng, Jian Zhou
Abstract: We demonstrate that the longitudinal single target-spin asymmetry in exclusive $\pi^0$ production in $ep$ collisions can give access to the imaginary part of the gluon generalized transverse momentum distribution (GTMD) $F_{1,4}$. Such a longitudinal spin asymmetry that results from the Coulomb-nuclear interference effect, leads to a characteristic azimuthal angular correlation of $\sin 2\phi$, where $\phi$ is the azimuthal angle between the scattered lepton transverse momentum and the recoiled proton's transverse momentum. We also present a numerical estimate of the asymmetry for the kinematics accessible at EIC and EicC.
6.Detecting axion dark matter with Rydberg atoms via induced electric dipole transitions
Authors:Georg Engelhardt, Amit Bhoonah, W. Vincent Liu
Abstract: Long-standing efforts to detect axions are driven by two compelling prospects, naturally accounting for the absence of charge-conjugation and parity symmetry breaking in quantum chromodynamics, and for the elusive dark matter at ultralight mass scale. Many experiments use the axion-photon coupling to probe the magnetic-field-mediated conversion of axions to photons. Here, we show that axion matter in a magnetic field induces electric dipole transitions in atoms and molecules. When applied to Rydberg atoms, which feature particularly large transition dipole elements, this effect promises an outstanding sensitivity for detecting ultralight dark matter. Our estimates show that it outperforms current experiments and other theoretical approaches based on axion-photon conversion by several orders of magnitude. The Rydberg atomic gases offer a flexible and inexpensive experimental platform that can operate at room temperature. We project the sensitivity by quantizing the axion-modified Maxwell equations to accurately describe atoms and molecules as quantum sensors wherever axion dark matter is present.
7.Dispersive determination of electroweak-scale masses
Authors:Hsiang-nan Li
Abstract: We demonstrate that the Higgs boson mass can be extracted from the dispersion relation obeyed by the correlation function of two $b$-quark scalar currents. The solution to the dispersion relation with the input from the perturbative evaluation of the correlation function up to next-to-leading order in QCD and with the $b$ quark mass $m_b=4.43$ GeV demands a specific Higgs mass 115 GeV. Our observation offers an alternative resolution to the long-standing fine-tuning problem of the Standard Model (SM): the Higgs mass is determined dynamically for the internal consistency of the SM. The similar formalism, as applied to the correlation function of two $b$-quark vector currents with the same $m_b$, leads to the $Z$ boson mass 90.8 GeV. This solution exists only when the $Z$ and $W$ boson masses are proportionate, conforming to the Higgs mechanism of the electroweak symmetry breaking. We then consider the mixing between the $Q\bar u$ and $\bar Qu$ states for a fictitious heavy quark $Q$ and a $u$ quark through the $b\bar b$ channel, inspired by our earlier analysis of neutral meson mixing. Its dispersion relation, given the perturbative input from the responsible box diagrams and the same $m_b$, fixes the top quark mass 177 GeV. It is highly nontrivial to predict the above electroweak-scale masses with at most 8\% deviation from their measured values using the single parameter $m_b$. More accurate results are expected, as more precise perturbative inputs are adopted.
8.Self-resonant Dark Matter
Authors:Hyun Min Lee
Abstract: We present a review on the self-resonant dark matter scenarios where multiple components of dark matter give rise to a resonant condition in the $u$-channel diagrams for their comparable masses. In this case, there is no need of lighter mediators for enhancing the self-scattering and annihilation cross sections for dark matter. We discuss the velocity-dependent self-scattering for the small-scale problems, the relic density of self-resonant dark matter, and the observable signatures in indirect and detection experiments.
9.Modular flavour symmetry and orbifolds
Authors:Francisco J. de Anda, Stephen F. King
Abstract: We develop a bottom-up approach to flavour models which combine modular symmetry with orbifold constructions. We first consider a 6d orbifold $\mathbb{T}^2/\mathbb{Z}_N$, with a single torus defined by one complex coordinate $z$ and a single modulus field $\tau$, playing the role of a flavon transforming under a finite modular symmetry. We then consider 10d orbifolds with three factorizable tori, each defined by one complex coordinate $z_i$ and involving the three moduli fields $\tau_1, \tau_2, \tau_3$ transforming under three finite modular groups. Assuming supersymmetry, consistent with the holomorphicity requirement, we consider all 10d orbifolds of the form $(\mathbb{T}^2)^3/(\mathbb{Z}_N\times\mathbb{Z}_M)$, and list those which have fixed values of the moduli fields (up to an integer). The key advantage of such 10d orbifold models over 4d models is that the values of the moduli are not completely free but are constrained by geometry and symmetry. To illustrate the approach we discuss a 10d modular seesaw model with $S_4^3$ modular symmetry based on $(\mathbb{T}^2)^3/(\mathbb{Z}_4\times\mathbb{Z}_2)$ where $\tau_1=i,\ \tau_2=i+2$ are constrained by the orbifold, while $\tau_3=\omega$ is determined by imposing a further remnant $S_4$ flavour symmetry, leading to a highly predictive example in the class CSD$(n)$ with $n=1-\sqrt{6}$.
10.HighTEA: High energy Theory Event Analyser
Authors:Michał Czakon, Zahari Kassabov, Alexander Mitov, Rene Poncelet, Andrei Popescu
Abstract: We introduce HighTEA, a new paradigm for deploying fully-differential next-to-next-to leading order (NNLO) calculations for collider observables. In principle, any infrared safe observable can be computed and, with very few restrictions, the user has complete freedom in defining their calculation's setup. For example, one can compute generic n-dimensional distributions, can define kinematic variables and factorization/renormalization scales, and can modify the strong coupling and parton distributions. HighTEA operates on the principle of analyzing precomputed events. It has all the required hardware and software infrastructure such that users only need to request their calculation via the internet before receiving the results, typically within minutes, in the form of a histogram. No specialized knowledge or computing infrastructure is required to fully utilize HighTEA, which could be used by both experts in particle physics and the general public. The current focus is on all classes of LHC processes. Extensions beyond NNLO, or to $e^+e^-$ colliders, are natural next steps.
11.GRANIITTI: towards a deep learning-enhanced Monte Carlo event generator for high-energy diffraction
Authors:Mikael Mieskolainen
Abstract: We introduce GRANIITTI, a new Monte Carlo event generator designed especially to solve the enigma of glueballs at the LHC. We discuss the available physics processes, compare the simulations against STAR data from RHIC and span ambitious future directions towards the first diffractive event generator with a deep learning-enhanced computational engine.
1.CKM and PMNS mixing matrix from $SO(2)$ flavor symmetry
Authors:Guojun Xu, Ying Zhang
Abstract: The relation between quark masses and CKM mixing is studied based on an approximate chiral $SO(2)_L\times SO(2)_R$ flavor symmetry of quark mass matrix. In mass hierarchy limit, the mass ratio effect to CKM mixing is suppressed, which separates mass hierarchy and quark flavor mixing into two independent problems. We show that CKM mixing is dominated by two left-handed $SO(2)_L^{u,d}$ symmetry while mass hierarchy only provides slight corrections. The same mixing structure is generalized to lepton sector with extended Dirac neutrinos. The common flavor mixing provides a novel comprehension on the relation between quark CKM mixing and lepton PMNS mixing.
2.Transverse momentum structure of strange and charmed baryons: a light-front Hamiltonian approach
Authors:Zhimin Zhu, Tiancai Peng, Zhi Hu, Siqi Xu, Chandan Mondal, Xingbo Zhao, James P. Vary, BLFQ Collaboration
Abstract: Under the basis light-front quantization framework, we investigate the leading-twist transverse-momentum-dependent parton distribution functions (TMDs) for $\Lambda$ and $\Lambda_c$ baryons, the spin-1/2 composite systems consisting of two light quarks ($u$ and $d$) and a $s/c$ quark. We evaluate the TMDs using the overlaps of the light-front wave functions in the leading Fock sector, which are obtained by solving the light-front eigenvalue equation. We also study the spin densities of quarks in momentum space for various polarizations. In the same model, we compare the TMDs of the strange and charmed baryons and the proton by reviewing their spin structures in the quark model and the probabilistic interpretations of their TMDs.
3.Quasicrystals in QCD
Authors:Zebin Qiu, Muneto Nitta
Abstract: We study the ground state of the low energy dense QCD with the assumption of chiral condensates of quarks. Under an external magnetic field, mesons could form soliton lattices via the chiral anomaly. For such scenarios, we present a unified description of pions and $\eta$ meson with a $U(2)$ field in the framework of the chiral perturbation theory. Our result shows the ground state is a mixture of the magnetized domain walls formed by neutral pion $\pi^0$ and $\eta$ meson when they coexist. The winding number of the ground state would alter according to the strength of the magnetic field. When the magnetic field is strong or the chemical potential is large, the proportion of the mixture is determined by the decay constants and the contributions to the anomalous action of $\pi^0$ and $\eta$ meson. The resulting configuration is either a mixed soliton lattice or a quasicrystal which could be dubbed a ``chiral soliton quasicrystal''.
4.Investigation of $Ω_{ccb}$ and $Ω_{cbb}$ baryons in Regge phenomenology
Authors:Juhi Oudichhya, Keval Gandhi, Ajay kumar Rai
Abstract: Triply heavy baryons with quark content $ccb$ and $cbb$ are investigated within the framework of Regge phenomenology. With the assumption of linear Regge trajectories, we have extracted the relations between Regge parameters and baryon masses. Using these relations, we compute the ground state masses of $\Omega_{ccb}$ and $\Omega_{cbb}$ baryons. Further, the Regge slopes and intercepts are estimated for these baryons to obtain the excited state masses in the $(J,M^{2})$ and $(n,M^{2})$ planes. \textbf{Also, using the obtained results we calculate the other properties like magnetic moment and radiative decay width of these triply heavy baryons.} We compare our evaluated results with those obtained by the other theoretical approaches, and our results show a general agreement with them. The present study and our predictions will provide significant clues for future experimental research of these unseen triply heavy baryons.
5.Configurational information measure of mesonic states in 4-flavor AdS/QCD
Authors:G. Karapetyan, W. de Paula, R. da Rocha
Abstract: Strange axial-vector kaons, $K_1$, and $f_1$ meson resonances are investigated in the 4-flavor AdS/QCD model. Their underlying differential configurational entropy is computed and the mass spectra of higher-excited resonances, in both these mesonic families, are achieved and discussed. This technique merges the 4-flavor AdS/QCD and experimental data regarding the mass spectrum of $K_1$ and $f_1$ meson resonances that have been already detected and reported in the Particle Data Group, also bringing forth a route to explore physical features of the next generation of resonances in the $K_1$ and $f_1$ meson families.
6.Thermodynamics of a rotating hadron resonance gas with van der Waals interaction
Authors:Kshitish Kumar Pradhan, Bhagyarathi Sahoo, Dushmanta Sahu, Raghunath Sahoo
Abstract: Studying the thermodynamics of the systems produced in ultra-relativistic heavy-ion collisions is crucial in understanding the QCD phase diagram. Recently, a new avenue has opened regarding the implications of large initial angular momentum and subsequent vorticity in the medium evolution in high-energy collisions. This adds a new type of chemical potential into the partonic and hadronic systems, called the rotational chemical potential. We study the thermodynamics of an interacting hadronic matter under rotation, formed in an ultra-relativistic collision. We introduce attractive and repulsive interactions through the van der Waals equation of state. Thermodynamic properties like the pressure ($P$), energy density ($\varepsilon$), entropy density ($s$), trace anomaly ($(\varepsilon - 3P)/T^{4}$), specific heat ($c_{\rm v}$) and squared speed of sound ($c_{\rm s}^{2}$) are studied as functions of temperature ($T$) for zero and finite rotation chemical potential. The charge fluctuations, which can be quantified by their respective susceptibilities, are also studied. The rotational (spin) density corresponding to the rotational chemical potential is explored. In addition, we explore the possible liquid-gas phase transition in the hadron gas with van der Waals interaction in the $T$ -- $\omega$ phase space.
7.Solving the domain wall problem with first-order phase transition
Authors:Yang Li, Ligong Bian, Yongtao Jia
Abstract: Domain wall networks are two-dimensional topological defects generally predicted in many beyond standard model physics. In this Letter, we propose to solve the domain wall problem with the first-order phase transition. We numerically study the phase transition dynamics, and for the first time show that the domain walls reached scaling regime can be diluted through the interaction with vacuum bubbles during the first-order phase transition. We find that the amplitude of the gravitational waves produced by the second-stage first-order phase transition is several orders higher than that from the domain walls evolution in the scaling regime. The scale of the first-order phase transition that dilute the domain walls can be probed through gravitational waves detection.
8.Is $f_2(1950)$ the tensor glueball?
Authors:Arthur Vereijken, Shahriyar Jafarzade, Milena Piotrowska, Francesco Giacosa
Abstract: Glueballs remain an experimentally undiscovered expectation of QCD. Lattice QCD (As well as other theoretical approaches) predicts a spectrum of glueballs, with the tensor ($J^{PC}=2^{++}$) glueball being the second lightest, behind the scalar glueball. Here, using a chiral hadronic model, we compute decay ratios of the tensor glueball into various meson decay channels. We find the tensor glueball to primarily decay into two vector mesons, dominated by $\rho \rho $ and $K^*K^*$ channels. These results are compared to experimental data of decay rates of isoscalar tensor mesons. Based on this comparison, we make statements on the eligibility of these mesons as potential tensor glueball candidates: the resonance $f_2(1950)$ turns out to be, at present, the best match as being predominantly a tensor glueball.
9.Unified description of the productions of $\bar{D}^*D$ and $\bar{D}^*D^*$ molecules in $B$ decays
Authors:Qi Wu, Ming-Zhu Liu, Li-Sheng Geng
Abstract: The exotic states $X(3872)$ and $Z_c(3900)$ have long been conjectured as isoscalar and isovector $\bar{D}^*D$ molecules, respectively. In this letter, we propose a unified framework to understand the productions of $\bar{D}^*D$ molecules as well as their heavy quark spin symmetry partners, $\bar{D}^*D^*$ molecules, in $B$ decays. We show that the large isospin breaking of the ratio $\mathcal{B}[B^+ \to X(3872) K^+]/\mathcal{B}[B^0 \to X(3872) K^0] $ can be attributed to the isospin breaking of the $\bar{D}^*D$ neutral and charged components. Because of this, the branching fractions of $Z_c(3900)$ in $B$ decays are smaller than the corresponding ones of $X(3872)$ by at least one order of magnitude, which naturally explains the non-observation of $Z_{c}(3900)$ in $B$ decays. Furthermore, we predict a hierarchy for the productions fractions of all the $\bar{D}^*D$ and $\bar{D}^*D^*$ molecules in $B$ decays, which are consistent with all the existing data and can help elucidate the internal structure of the $XZ$ states around the $\bar{D}^*D$ and $\bar{D}^*D^*$ mass thresholds, if confirmed by future experiments.
1.Testing CP-violation in a Heavy Higgs Sector at CLIC
Authors:Kingman Cheung, Ying-nan Mao, Stefano Moretti, Rui Zhang
Abstract: We propose a novel method to test CP-violation in the heavy (pseudo)scalar sector of an extended Higgs model, in which we make simultaneous use of the $HVV$ ($V=W^\pm, Z$) and $Ht\bar{t}$ interactions of a heavy Higgs state $H$. This is possible at the Compact Linear Collider (CLIC) by exploiting $H$ production from Vector-Boson Fusion (VBF) and decay to $t\bar{t}$ pairs. We analyze the distribution of the azimuthal angle between the leptons coming from top and antitop quarks, that would allow one to disentangle the CP nature of such a heavy Higgs state. We also show its implications for the 2-Higgs-Doublet Model (2HDM) with CP-violation.
2.Rotation and vibration in tetraquarks
Authors:Amir Jalili, Jorge Segovia, Feng Pan, Yan-An Luo
Abstract: A novel approach is introduced for obtaining precise solutions of the pairing Hamiltonian for tetraquarks, which utilizes an algebraic technique in infinite dimensions. The parameters involved in the transition phase are calibrated based on potential tetraquark candidates derived from phenomenology. Our investigation shows that the rotation and vibration transitional theory delivers a more accurate explanation for heavy tetraquarks compared to other methods utilizing the same formalism. To illustrate the concept, we compute the spectra of several tetraquarks, namely charm, bottom, bottom-charm and open charm and bottom systems, and contrast them with those of other particles.
3.Updated Constraints and Future Prospects on Majoron Dark Matter
Authors:Kensuke Akita, Michiru Niibo
Abstract: Majorons are (pseudo-)Nambu-Goldstone bosons associated with lepton number symmetry breaking due to the Majorana mass term of neutrinos introduced in the seesaw mechanism. They are good dark matter candidates since their lifetime is suppressed by the lepton number breaking scale. We update constraints and discuss future prospects on majoron dark matter in the singlet majoron models based on neutrino, gamma-ray, and cosmic-ray telescopes in the mass region of MeV--10 TeV.
4.Unparticle effects at the MUonE experiment
Authors:Duc Ninh Le, Van Dung Le, Duc Truyen Le, Van Cuong Le
Abstract: We investigate possible effects of unparticles at the MUonE experiment by considering a general model for unparticle with broken scale invariance, characterized by the scaling dimension $d$ and the energy scale $\mu$ at which the scale invariance is broken. Taking into account available relevant constraints on the couplings of the unparticles with the Standard Model (SM) leptons, we found that the MUonE experiment at the level of 10 ppm systematic accuracy is sensitive to such effects if $1<d\lesssim 1.4$ and $1\le \mu \lesssim 12$ GeV for vector unparticles. The effects of scalar unparticles are too feeble to be detected. The vector unparticles can induce a significant shift on the best-fit value of $a_\mu^\text{had}$ at the MUonE, thereby providing an opportunity to detect unparticles or to obtain a new bound on the unparticle-SM couplings in the case of no anomaly.
5.Variation of the quadrupole hyperfine structure and nuclear radius due to an interaction with scalar and axion dark matter
Authors:V. V. Flambaum, A. J. Mansour
Abstract: Atomic spectroscopy is used to search for the space-time variation of fundamental constants which may be due to an interaction with scalar and pseudo-scalar (axion) dark matter. In this letter, we study the effects which are produced by the variation of the nuclear radius and electric quadrupole moment. The sensitivity of the electric quadrupole hyperfine structure to both the variation of the quark mass and the effects of dark matter exceeds that of the magnetic hyperfine structure by 1-2 orders of magnitude. Therefore, the measurement of the variation of the ratio of the electric quadrupole and magnetic dipole hyperfine constants is proposed. The sensitivity of the optical clock transitions in the Yb$^+$ ion to the variation of the nuclear radius allows us to extract, from experimental data, limits on the variation of the hadron and quark masses, the QCD parameter $\theta$ and the interaction with axion and scalar dark matter.
6.Searching for Majorana Neutrinos at a Same-Sign Muon Collider
Authors:Ruobing Jiang, Tianyi Yang, Sitian Qian, Yong Ban, Jingshu Li, Zhengyun You, Qiang Li
Abstract: Majorana properties of neutrinos have long been a focus in the pursuit of possible new physics beyond the standard model, which has motivated lots of dedicated theoretical and experimental studies. A future same-sign muon collider is an ideal platform to search for Majorana neutrinos through the Lepton Number Violation process. Specifically, this t-channel kind of process is less kinematically suppressed and has a good advantage in probing Majorana neutrinos at high mass regions up to 10 TeV. In this paper, we perform a detailed fast Monte Carlo simulation study through examining three different final states: 1) pure-leptonic state with electrons or muons, 2) semi-leptonic state, and 3) pure-hadronic state in the resolved or merged categories. Furthermore, we perform a full simulation study on the pure-leptonic final state to validate our fast simulation results.
7.Chiral perturbative relation for neutrino masses in the type-I seesaw mechanism
Authors:Masaki J. S. Yang
Abstract: In this letter, we perform a perturbative analysis by the lightest singular value $m_{D1}$ of the Dirac mass matrix $m_{D}$ in the type-I seesaw mechanism. As a result, the mass $M_{1}$ of the lightest right-handed neutrino $\nu_{R1}$ is expressed as $M_{1} = m_{D1}^{2}/ |(m_{\nu})_{11}|$ by the mass matrix of the left-handed neutrinos $m_{\nu}$ in the diagonal basis of $m_{D}$. Since $m_{D1} \sim 1$ MeV and $|(m_{\nu})_{11}| \sim 1$ meV lead to $M_{1} \sim 10^{6}$ GeV, such a $\nu_{R1}$ with a tiny Yukawa coupling $y_{\nu 1} \sim O(10^{-5})$ may indirectly influence observations of IceCube. On the other hand, the famous bound of the thermal leptogenesis $M_{1} \gtrsim 10^{9}$ GeV that requires $m_{D1} \gtrsim 30$ MeV seems to be difficult to reconcile with a simple unified theory.
8.MSSM-inflation revisited: Towards a coherent description of high-energy physics and cosmology
Authors:Gilles Weymann-Despres, Sophie Henrot-Versillé, Gilbert Moultaka, Vincent Vennin, Laurent Duflot, Richard von Eckardstein
Abstract: The aim of this paper is to highlight the challenges and potential gains surrounding a coherent description of physics from the high-energy scales of inflation down to the lower energy scales probed in particle-physics experiments. As an example, we revisit the way inflation can be realised within an effective Minimal Supersymmetric Standard Model (eMSSM), in which the $LLe$ and $udd$ flat directions are lifted by the combined effect of soft-supersymmetric-breaking masses already present in the MSSM, together with the addition of effective non-renormalizable operators. We clarify some features of the model and address the question of the one-loop Renormalization Group improvement of the inflationary potential, discussing its impact on the fine-tuning of the model. We also compare the parameter space that is compatible with current observations (in particular the amplitude, $A_{\scriptscriptstyle{\mathrm{S}}}$, and the spectral index, $n_{\scriptscriptstyle{\mathrm{S}}}$, of the primordial cosmological fluctuations) at tree level and at one loop, and discuss the role of reheating. Finally we perform combined fits of particle and cosmological observables (mainly $A_{\scriptscriptstyle{\mathrm{S}}}$, $n_{\scriptscriptstyle{\mathrm{S}}}$, the Higgs mass, and the cold-dark-matter energy density) with the one-loop inflationary potential applied to some examples of dark-matter annihilation channels (Higgs-funnel, Higgsinos and A-funnel), and discuss the status of the ensuing MSSM spectra with respect to the LHC searches.
9.Resolve negative cross section of quarkonium hadroproduction using soft gluon factorization
Authors:An-Ping Chen, Yan-Qing Ma, Ce Meng
Abstract: It was found that, using NRQCD factorization, the predicted $\chi_{cJ}$ hadroproduction cross section at large $p_T$ can be negative. The negative cross sections originate from terms proportional to plus function in ${^{3}\hspace{-0.6mm}P_{J}^{[1]}}$ channels, which are remnants of the infrared subtraction in matching the ${^{3}\hspace{-0.6mm}P_{J}^{[1]}}$ short-distance coefficients. In this article, we find that the above terms can be factorized into the nonperturbative ${^{3}\hspace{-0.6mm}S_{1}^{[8]}}$ soft gluon distribution function in the soft gluon factorization (SGF) framework. Therefore, the problem can be naturally resolved in SGF. With an appropriate choice of nonperturbative parameters, the SGF can indeed give positive predictions for $\chi_{cJ}$ production rates within the whole $p_T$ region. The production of $\psi(2S)$ is also discussed, and there is no negative cross section problem.
10.Leptogenesis and Dark Matter-Nucleon Scattering Cross Section in the SE6SSM
Authors:Roman Nevzorov
Abstract: The E6 inspired extension of the minimal supersymmetric (SUSY) standard model (MSSM) with an extra U(1)_N gauge symmetry, under which right-handed neutrinos have zero charge, involves exotic matter beyond the MSSM to ensure anomaly cancellation. We consider the variant of this extension (SE6SSM) in which the cold dark matter is composed of the lightest neutral exotic fermion and gravitino. The observed baryon asymmetry can be induced in this case via the decays of the lightest right-handed neutrino/sneutrino into exotic states even for relatively low reheating temperatures T_R < 10^{6-7} GeV. We argue that there are some regions of the SE6SSM parameter space, which are safe from all current constraints, and discuss the implications of this model for collider phenomenology.
11.On the IR/UV flavour connection in non-universal axion models
Authors:Luca Di Luzio, Alfredo Walter Mario Guerrera, Xavier Ponce Díaz, Stefano Rigolin
Abstract: Non-universal axion models, with the Peccei-Quinn (PQ) symmetry acting on Standard Model (SM) fermions in a generation-dependent way, are typically accompanied by two different sources of flavour violation, dubbed here as infrared (IR) and ultraviolet (UV). The former is due to the flavour violating axion couplings to SM fermions, while the latter arises from the heavy degrees of freedom that UV complete the axion effective field theory. We point out that these two sources of flavour violation are directly related and exemplify this connection in a general class of non-universal axion model, based on a renormalizable DFSZ-like setup with two Higgs doublets (PQ-2HDM). We next discuss the interplay of axion flavour phenomenology with the signatures stemming from the heavy radial modes of the PQ-2HDM, including meson oscillation observables and charged lepton flavour violating decays. We emphasize the strong complementarity between flavour observables, LHC direct searches and standard axion physics.
12.There and back again: Solar cycle effects in future measurements of low-energy atmospheric neutrinos
Authors:Kevin J. Kelly, Pedro A. N. Machado, Nityasa Mishra, Louis E. Strigari, Yi Zhuang
Abstract: We study the impact of time-dependent solar cycles in the atmospheric neutrino rate at DUNE and Hyper-Kamiokande (HK), focusing in particular on the flux below 1 GeV. Including the effect of neutrino oscillations for the upward-going component that travels through the Earth, we find that across the solar cycle the amplitude of time variation is about $\pm5\%$ at DUNE, and $\pm 1\%$ at HK. At DUNE, the ratio of up/down-going events ranges from 0.45 to 0.85, while at HK, it ranges from 0.75 to 1.5. Over the 11-year solar cycle, we find that the estimated statistical significance for observing time modulation of atmospheric neutrinos is $4.8\sigma$ for DUNE and $2.0\sigma$ for HK. Flux measurements at both DUNE and HK will be important for understanding systematics in the low-energy atmospheric flux as well as for understanding the effect of oscillations in low-energy atmospheric neutrinos.
13.A Solar Investigation of Multicomponent Dark Matter
Authors:Amit Dutta Banik
Abstract: If multiple thermal weakly interacting massive particle (WIMP) dark matter candidates exist, then their capture and annihilation dynamics inside a massive stars such as Sun could change from conventional method of study. With a simple correction to time evolution of dark matter (DM) number abundance inside the Sun for multiple dark matter candidates, significant changes in DM annihilation flux depending on annihilation, direct detection cross-section, internal conversion and their contribution to relic abundance are reported in present work.
14.Primordial Black Hole Archaeology with Gravitational Waves from Cosmic Strings
Authors:Anish Ghoshal, Yann Gouttenoire, Lucien Heurtier, Peera Simakachorn
Abstract: Light primordial black holes (PBHs) with masses smaller than $10^9$ g ($10^{-24} M_\odot$) evaporate before the onset of Big-Bang nucleosynthesis, rendering their detection rather challenging. If efficiently produced, they may have dominated the universe energy density. We study how such an early matter-dominated era can be probed successfully using gravitational waves (GW) emitted by local and global cosmic strings. While previous studies showed that a matter era generates a single-step suppression of the GW spectrum, we instead find a "double-step" suppression for local-string GW whose spectral shape provides information on the duration of the matter era. The presence of the two steps in the GW spectrum originates from GW being produced through two events separated in time: loop formation and loop decay, taking place either before or after the matter era. The second step - called the "knee" - is a novel feature which is universal to any early matter-dominated era and is not only specific to PBHs. Detecting GWs from cosmic strings with LISA, ET, or BBO would set constraints on PBHs with masses between $10^6$ and $10^9$ g for local strings with tension $G\mu = 10^{-11}$, and PBHs masses between $10^4$ and $10^9$ g for global strings with symmetry-breaking scale $\eta = 10^{15}~\mathrm{GeV}$. Effects from the spin of PBHs are discussed.