Properties of hybrid stars with hadron–quark crossover

Abstract

The properties of hybrid stars are studied via the hybrid EOSs that are compatible with astrophysical observables. These hybrid EOSs are constructed by interpolating between hadronic EOS at lower densities and the quark EOS at higher densities. The BSR6 EOS derived from the RMF model is adopted as the hadronic EOS, while the quark EOS is calculated via a quasiparticle model. The maximum masses obtained from the hybrid EOSs are larger than [Formula: see text], and the tidal deformabilities for [Formula: see text] hybrid stars are smaller than 800. The combined tidal deformability [Formula: see text] is a monotonically increasing function of mass ratio [Formula: see text] for both hybrid EOSs and hadronic EOS, and it depends weakly on [Formula: see text]. The results of all hybrid EOSs can strictly satisfy the constraint of [Formula: see text] and the mass and radius constraints from the newest joint analysis of NICER, XMM-Newton and GW170817 data.