PSR J$0952-0607$ and GW170817: Direct Multimessenger Constraints on Neutron Star Equation of State through a Novel Wide-ranging Correlation

Abstract

Our knowledge about neutron star (NS) masses is renewed once again due to the recognition of the heaviest NS PSR J$ 0952-0607 $. By taking advantage of both mass observations of super massive neutron stars and the tidal deformability derived from event GW170817, a joint constraint on tidal deformability is obtained. A wide-ranging correlation between NS pressure and tidal deformability within the density range from saturation density $\rho_0$ to $5.6\rho_0$ is discovered, which directly yields a constrained NS EoS. The newly constrained EoS has a small uncertainty and a softer behavior at high densities without the inclusion of extra degrees of freedom, which shows its potential to be used as an indicator for the component of NS core.