报告题目: GRB 170817A associated with GW170817: a short GRB seen off-axis?

报告人：何新波（中山大学）

时间：12月1日（周五）上午11：00

地点：理学实验楼718

摘要：

The leading theory for short-duration GRBs is neutron star-neutron star (NS-NS) mergers or black hole-NS mergers, while bursts of soft gamma-ray repeaters (SGRs) in a nearby galaxy may mimic a short GRB. If a short GRB due to a merger occur in the local Universe, the merger event can simultaneously produce gravitational wave signal detectable by current detectors like advanced LIGO/Virgo, while no detectable signal is expected for an SGR. Recently, Fermi GBM detected a short GRB 170817A. It is associated with a binary neuron star merger event detect by LIGO/Virgo, GW170817. The isotropic-equivalent γ-ray energetics, Eiso,γ of GRB 170817A is only about 4*10^46 erg, much lower than a typical cosmological short GRB. So it will be the first low-luminosity GRB of short duration. An interesting explanation is that it is an off-axis short GRB with structured jets.