Mar 7

Electromagnetic counterparts of compact binary mergers

Martedì 12 Marzo 2019 alle ore 11:00, presso l’Aula Seminari dell’Osservatorio, il dott. Stefano Ascenzi del GSSI – Gran Sasso Science Institute terrà un seminario dal titolo “Electromagnetic counterparts of compact binary mergers“.

Abstract

Compact binary systems composed by neutron stars (NS) and black holes (BH) are one of the principal sources of gravitational waves (GW) in the terrestrial interferometers frequency range (10 Hz -1 kHz). While BH binary coalescences are not expected in general to be accompanied by any electromagnetic signal, detectable electromagnetic (EM) counterparts, such as Short Gamma-Ray Bursts (SGRB) and Kilonovae (KNe), could follow binary NS and NS-BH mergers. The recent joint GW and electromagnetic observation of a binary NS coalescence (GW170817) marked the down of multi-messenger astronomy era that open a new way to explore the high energetic universe and test the fundamental physics under extreme conditions. The coincident detection of gravitational and electromagnetic radiation is important because these messengers carry different and complementary information: while from a GW detection it is possible to infer the masses and the spins of the binary progenitors, electromagnetic emission is essential to localize the source, thus enabling the host galaxy identification.

In this talk, after a brief description of the merger dynamics, I will describe three different EM counterparts of compact binary mergers, such as SGRBs, KNe and Spindown-powered transients (SDPTs). In particular, I will discuss how it is possible to infer from a sample of SGRBs a luminosity distribution for KNe and I will also show the preliminary results of my work of hydrodynamic simulations of SDPTs. Finally, I will describe a new method to measure NS radii -and thus to constrain the dense matter equation of state – exploiting joint detections of SGRB and GW from a NS-BH progenitors.

 

VIDEO del SEMINARIO sul CANALE YouTube dell’Osservatorio Astronomico d’Abruzzo

 

Comments are closed.