Gravitational Waves

"Binary Neutron Star Mergers in the QCD Phase Diagram" by Matthias Hanauske (Goethe University Frankfurt)



The long-awaited detection of a gravitational wave (GW) from the merger of a binary neutron star in August 2017 (GW170817) marks the beginning of the new field of multi-messenger gravitational wave astronomy. Exploiting the extracted tidal deformations of the two neutron stars from the late inspiral phase of GW170817 it is now possible to severely constrain several global properties of the equation of state (EOS) of neutron star matter. However, the most interesting part of the high density and temperature regime of the EOS is solely imprinted in the post-merger GW emission from the remnant hypermassive/supramassive neutron star (HMNS/SMNS). This regime was not observed in GW170817, but will possibly be detected in forthcoming events within the next observing run. Based on a large number of numerical-relativity simulations of merging neutron star binaries, the emitted GWs, the interior structure of the generated HMNS/SMNS and the evolution of the underlying matter of the remnant in the phase diagram of quantum chromodynamics (QCD phase diagram) have been analyzed in detail. This talk will focus on the consequences of a potential appearance of a hadron-quark phase transition in the interior region of the produced HMNS/SMNS and its connection with the spectral properties of the emitted GW.