Description:

Francois Foucart
Lawrence Berkeley National Laboratory

Electromagnetic and gravitational wave signals from merging black holes and neutron stars

Black hole-neutron star and neutron star-neutron star mergers are powerful emitters of gravitational waves, and can produce a wide range of bright electromagnetic transients. They also provide us with a remarkable environment to study nuclear interactions in the cold, dense core of neutron stars, and may significantly contribute to the production of many heavy elements whose origin remains unexplained. Given the increasing sensitivity of existing gravitational wave detectors, we expect gravitational waves from neutron star mergers to be observed in the coming years. In order to extract as much information as possible from these observations, reliable models of the gravitational wave and electromagnetic signals powered by mergers are necessary. In this talk, I will discuss our efforts to study binary mergers using general relativistic simulations. I will in particular focus on recently developed gravitational wave models which account for tidal effects in neutron stars, on the electromagnetic transients powered by radioactive decays in the matter ejected by neutron star mergers, and on the outcome of nucleosynthesis in that ejecta. Tidal effects in neutron star mergers can provide us with information about the size of neutron stars, an important observable in nuclear physics, while radioactively powered transients can offer both improved localization of the merger events and additional information about the properties of the merging objects.

Host: Fred Rasio