Cafe Club

Pavan VYNATHEYA (Max Planck Institut für Astrophysik, MPA, Garching): “Gravitational waves from quadruple stars – quadruple the fun (?)”

The cafe-club will take place at 11:00 on zoom AMU virtual room.

You can find the schedule of upcoming café-clubs and the video of old ones on the Cafe Club wiki

Take care,
Carlo, Mathilde, Meriam

ABSTRACT

Mergers of black holes (BHs) and neutron stars (NSs) result in the emission of gravitational waves that can be detected by LIGO. We look at 2+2 and 3+1 quadruple-star systems, which are common among massive stars, the progenitors of BHs and NSs. We carry out a detailed population synthesis of quadruple systems using the MSE code, which seamlessly takes into consideration stellar evolution, binary and tertiary interactions, N-body dynamics, and secular evolution. We find that, although secular evolution plays a role in compact object (BH and NS) mergers, (70–85) % (depending on the model assumptions) of the mergers are solely due to common envelope (CE) evolution. When kicks are taken into account, there are no systems that evolve into a quadruple consisting of four compact objects. The BH-BH merger rates represent a significant fraction of the current LIGO rates, whereas the other merger rates fall short of LIGO estimates.