High Energy Astrophysical Phenomena (astro-ph.HE)
Fri, 07 Jul 2023
1.Deep Synoptic Array Science: First FRB and Host Galaxy Catalog
Authors:C. J. Law Caltech, Owens Valley Radio Observatory, K. Sharma Caltech, Owens Valley Radio Observatory, V. Ravi Caltech, Owens Valley Radio Observatory, G. Chen Caltech, Owens Valley Radio Observatory, M. Catha Caltech, Owens Valley Radio Observatory, L. Connor Caltech, Owens Valley Radio Observatory, J. T. Faber Caltech, Owens Valley Radio Observatory, G. Hallinan Caltech, Owens Valley Radio Observatory, C. Harnach Caltech, Owens Valley Radio Observatory, G. Hellbourg Caltech, Owens Valley Radio Observatory, R. Hobbs Caltech, Owens Valley Radio Observatory, D. Hodge Caltech, Owens Valley Radio Observatory, M. Hodges Caltech, Owens Valley Radio Observatory, J. W. Lamb Caltech, Owens Valley Radio Observatory, P. Rasmussen Caltech, Owens Valley Radio Observatory, M. B. Sherman Caltech, Owens Valley Radio Observatory, J. Shi Caltech, Owens Valley Radio Observatory, D. Simard Caltech, Owens Valley Radio Observatory, R. Squillace Caltech, Owens Valley Radio Observatory, S. Weinreb Caltech, Owens Valley Radio Observatory, D. P. Woody Caltech, Owens Valley Radio Observatory, N. Yadlapalli Caltech, Owens Valley Radio Observatory
Abstract: Fast Radio Bursts (FRBs) are a powerful and mysterious new class of transient that are luminous enough to be detected at cosmological distances. By associating FRBs to host galaxies, we can measure intrinsic and environmental properties that test FRB origin models, in addition to using them as precise probes of distant cosmic gas. The 110-antenna Deep Synoptic Array (DSA-110) is a radio interferometer built to maximize the rate at which it can simultaneously detect and localize FRBs. Here, we present the first sample of FRBs and host galaxies discovered by the DSA-110. This sample of 11 FRBs is the largest uniform sample of localized FRBs to date and is selected based on association to host galaxies identified in optical imaging by Pan-STARRS1 and follow-up spectroscopy at the Palomar and Keck observatories. These FRBs have not been observed to repeat and their radio properties (dispersion, temporal scattering, energy) are similar to that of the known non-repeating FRB population. Most host galaxies have ongoing star formation, as has been identified before for FRB hosts. In contrast to prior work, a large fraction (four of eleven) of the new sample are more massive than 10$^{11}$\ M$_{\odot}$ and most had elevated star formation rates more than 100 Myr in their past. The distribution of star-formation history across this host-galaxy sample shows that the delay-time distribution is wide, spanning from $\sim100$\,Myr to $\sim10$\,Gyr. This requires the existence of one or more progenitor formation channels associated with old stellar populations, such as the binary evolution of compact objects.
2.Molecular environment of the thermal composite supernova remnant G352.7$-$0.1
Authors:Qian-Qian Zhang, Ping Zhou, Yang Chen, Xiao Zhang, Wen-Juan Zhong, Xin Zhou, Zhi-Yu Zhang, Jacco Vink
Abstract: Galactic supernova remnants (SNRs) play an important role in our understanding of supernovae and their feedback on the interstellar environment. SNR G352.7$-$0.1 is special for its thermal composite morphology and double-ring structure. We have performed spectroscopic mapping in $^{12}$CO and $^{13}$CO $J=2$-1 lines toward G352.7$-$0.1 with the Atacama Pathfinder Experiment telescope. Broad $^{12}$CO lines are found in the northeastern ring at a local-standard-of-rest velocity range of $\sim-50$-$-30$ km s$^{-1}$, suggesting that the remnant is interacting with molecular clouds (MCs) at $\sim-51$ km s$^{-1}$. Thus, we adopt a distance of $\sim10.5$ kpc for this SNR. The momentum and kinetic energy of the shocked gas along the line of sight are estimated to be $\sim10^2{\rm M_{sun}}$ km s$^{-1}$ and $\sim10^{46}$ erg, respectively. We also find an expanding structure around the remnant, which is possibly related to the wind-blown bubble of the progenitor star. From the Fermi-LAT data in an energy range of 0.1-500 GeV, we find no gamma-ray counterparts of G352.7$-$0.1.