The rate, luminosity function and time delay of non-Collapsar short GRBs

Understand

We estimate the rate and the luminosity function of short (hard) Gamma-Ray Bursts (sGRBs) that are non-Collapsars, using the peak fluxes and redshifts of BATSE, Swift and Fermi GRBs.

• Following Bromberg2013 we select a sub-sample of Swift bursts which are most likely non-Collapsars.
• We find that these sGRBs are delayed relative to the global star formation rate (SFR) with a typical delay time of a 3-4 Gyr (depending on the SFR model).
• However, if two or three sGRB at high redshifts have been missed because of selection effects, a distribution of delay times of ~1/t would be also compatible.