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Gamma-ray bursts (GRBs for short) were discovered by accident during the cold war by satellites looking for signatures of nuclear detonations in the atmosphere. These brief explosions occur at the farthest reaches of the Universe, but here at Earth they can outshine all the gamma-ray sources while they last. According to our current understanding, GRBs mark the death of massive stars (few times 10 Solar masses) or the merger of two neutron stars. The Gamma-ray Burst Monitor (GBM) instrument aboard the Fermi Space Telescope constantly monitors the gamma-ray sky looking for GRBs and detects a new burst almost every day.
On August 17, 2017, our team announced the detection of a run-of-the-mill GRB, named GRB 170817A after the date of the discovery. Only 2 seconds before the GRB, the LIGO and Virgo instruments detected the merger of two neutron stars through gravitational waves. The two signals came from the same location in the sky from a source 130 million lightyears away and marked the first object "seen" in both electromagnetic radiation and gravitational waves. It also confirmed the binary neutron star merger origin for some gamma-ray bursts.
I will discuss the discovery of GRB 170817A and its implications in addition to other interesting developments in the field of GRBs.
Here you can play back the recording of the presentation
