Properties of hybrid stars with hadron-quark crossover

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 2 M-circle dot, and the tidal deformabilities for 1.4 M-circle dot hybrid stars are smaller than 800. The combined tidal deformability (Lambda) over tilde is a monotonically increasing function of mass ratio eta for both hybrid EOSs and hadronic EOS, and it depends weakly on eta. The results of all hybrid EOSs can strictly satisfy the constraint of 70 < <(Lambda)over tilde> < 720 and the mass and radius constraints from the newest joint analysis of NICER, XMM-Newton and GW170817 data.

Automated summary

The properties of hybrid stars are studied using hybrid EOSs that satisfy astrophysical observations. The maximum masses and tidal deformabilities of hybrid stars are found to meet the constraints, and the combined tidal deformability increases with mass ratio.