GRB Host Galaxies and Galaxy Evolution

Science Institute, University of Iceland, Dunhaga 3, IS–107 Reykjavik, Iceland

Abstract

Galaxy properties in general and properties of host galaxies of gamma-ray bursts (GRBs) in particular are investigated, using N-body/Eulerian hydrodynamic simulations and the stellar population synthesis model, Starburst99. We identify simulated galaxies that have optical star formation rate and SFR-to-luminosity ratio similar to those observed in a well-defined sample of ten host galaxies. The specific rates of the numerical counterparts are equal to or higher than the median values estimated at the different redshifts. At intermediate redshift, our overall population shows that the faintest and bluest galaxies are also the objects with the highest specific rates. These results suggest that GRB host galaxies are likely to be drawn from the high specific SFR sub-population of galaxies, rather than the high SFR galaxy population.