2005/09/30 by N. R. Tanvir, R. Chapman, A. J. Levan +1 · 5 citations
Physics and Astronomy · #Gamma-ray bursts and supernovae #Pulsars and Gravitational Waves Research #astro-ph
paper · pdf · doi:10.1038/nature04310
published as Nature 438:991-993,2005 · To appear in Nature, 15th December 2005. Replaced with published version
openalex publication_date 2005/12/01 · arxiv created 2005/12/14 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/01
Gamma-ray bursts (GRBs) divide into two classes: "long", which typically have initial durations of T90>2s, and "short", with durations of T90<2s (where T90 is the time to detect 90% of the observed fluence). Long bursts, which on average have softer gamma-ray spectra, are known to be associated with with stellar core-collapse events-- in some cases simultaneously producing powerful Type Ic supernovae. In contrast, the origin of short bursts has remained mysterious until recently. A subsecond intense "spike" of gamma-rays during a giant flare from the Galactic soft gamma-ray repeater, SGR 1806-20, reopened an old debate over whether some short GRBs could be similar events seen in galaxies out to ~70Mpc (redshift z=0.016). Shortly after that, localizations of a few short GRBs (with optical afterglows detected in two cases) have shown an apparent association with a variety of host galaxies at moderate redshifts. Here we report a correlation between the locations of previously observed short bursts and the positions of galaxies in the local Universe, indicating that between 10 and 25 per cent of short GRBs originate at low redshifts (z<0.025).