Astronomers develop extensive inventory to date of SGRBs' host galaxies

Researchers have developed the most extensive inventory to date of the galaxies where short gamma-ray bursts (SGRBs) - the brightest and most energetic phenomena in the known universe - originate. They also found that about 85% of the studied SGRBs come from young, actively star-forming galaxies.

Previously, astronomers characterized host galaxies from only a couple dozen SGRBs. The new catalog is quadruple the number of existing samples.

The catalog was created using several highly sensitive instruments at W.M. Keck Observatory, the Gemini Observatories, the MMT Observatory, the Large Binocular Telescope Observatory and the Magellan Telescopes at Las Campanas Observatory. The team also used data from NASA's Hubble Space Telescope and Spitzer Space Telescope.

"This is the largest catalog of SGRB host galaxies to ever exist, so we expect it to be the gold standard for many years to come. Building this catalog and finally having enough host galaxies to see patterns and draw significant conclusions is exactly what the field needed to push our understanding of these fantastic events and what happens to stars after they die," said Anya Nugent, a Northwestern graduate student who led the study focused on modeling host galaxies.

The Northwestern University-led team pinpointed the galactic homes of 84 SGRBs and probed the characteristics of 69 of the identified host galaxies. They also found that more SGRBs occurred when the universe was much younger and with greater distances from their host galaxies' centers than previously known.

The team published two papers, detailing the new catalog, today (Nov. 21) in The Astrophysical Journal.

With the wealth of data and results presented in the catalog of SGRB host galaxies, I believe a variety of research projects will make use of it, maybe even in ways we have yet not thought of," said Yuxin "Vic" Dong, study co-author and astrophysics Ph.D. student at Northwestern.