Short cosmic events: A subset of classical GRBs?

Abstract

During 28 months of operation, the French‐Soviet PHEBUS experiment onboard GRANAT has recorded a total of 66 cosmic γ‐ray bursts (GRBs). We observe that events lasting less than 2 seconds exhibit harder spectra both on average and at the maximum peak. Their peculiar spectral shape and their similarities in time history claim in favor of the existence of a separate class of short cosmic γ‐ray bursts.