摘要
Gamma-ray bursts(GRBs)are flashes of ganima-rays occurring at cosmological distances(for a recent review see^([1])).They are divided into two classes based on their prompt emission durations:short-duration(<2 seconds)hard-spectrum bursts and long-duration soft-spectmm bursts(>2 seconds).The observations(including discoveries of both the gravitational wave event GW170817 from an inspiral of two neutron stars and its electromagnetic counterparts)indicate that long-duration GRBs result from core collapses of massive stars and short-duration GRBs are produced from mergers of neutron star-neutron star binaries or black hole-neutron star binaries.
