Description:

Deciphering the Origins of the Universe’s Most Fantastic Explosions with State-of-the-Art Environmental Studies

Short gamma-ray bursts (GRBs; z~0.1-3), originate from neutron star (NS) mergers, thus are directly connected to the local population of gravitational wave mergers and contribute to the heavy “r-process” element enrichment of the Universe. Host galaxy studies of these events are imperative to understanding the necessary environmental conditions under which the progenitor can form, its merger timescale, and impact on the Universe’s chemical evolution. As short GRBs are both detected and associated to host galaxies far more frequently than GW NS events and extend to much further redshifts, their host population currently provides the most information on the formation and evolution of these systems. Here, I discuss building the largest catalog of short GRB host galaxy observations and stellar population properties, including redshifts, stellar masses, ages, metallicities and star formation rates.  Along with these host properties, I discuss the implications for the distribution of NS merger timescales. I further present a population of ultra-faint SGRB hosts which thus far had unknown redshifts, but provide strong discriminating power on their NS merger timescale distributions and chemical enrichment of the Universe. I conclude with recent efforts to constrain the fraction of stars within these host environments that can be enriched with r-process elements from these mergers to probe whether NS mergers are the dominant source of observed r-process elements in the Universe.