New High Energy Astrophysics Involving Gravitational Waves and Satellite Observations

A new exploration of the Universe has recently started through gravitational-wave observations. On September 14, 2015, the first detection of gravitational waves from the coalescence of a binary system of black holes by the Advanced LIGO detectors marked the dawn of gravitational-wave astronomy. On August 17, 2017, the first observation of gravitational waves from the inspiral and merger of a binary neutron-star system by the Advanced LIGO and Virgo network, followed 1.7 s later by a weak short gamma-ray burst detected by the Fermi and INTEGRAL satellites initiated the most extensive world-wide observing campaign which led to the detection of multi-wavelength electromagnetic counterparts. Multi-messenger discoveries are revealing the enigmas of the most energetic transients in the sky, probing relativistic astrophysics, nuclear physics, nucleosynthesis, and cosmology. The talk will give an overview of the astrophysical implications of the gravitational-wave and multi-messenger observations, focusing on the key role of multi-wavelength satellites operating together with the current and future gravitational-wave detectors.