Equation of state for hybrid compact stars with a nonlocal chiral quark model

TL;DR

This paper develops an equation of state for hybrid compact stars using a nonlocal chiral quark model, incorporating color superconductivity and phase transitions to hadronic matter, resulting in models consistent with observed massive neutron stars.

Contribution

It introduces a nonlocal chiral quark model for hybrid stars with detailed thermodynamics and phase transition modeling, aligning theoretical predictions with observational data.

Findings

Mass-radius relations exceed 2 solar masses

Phase transition modeled with Dirac-Brueckner-Hartree-Fock approach

Hybrid star configurations meet current observational constraints

Abstract

We study the thermodynamics of two flavor color superconducting (2SC) quark matter within a nonlocal chiral quark model, using both instantaneous and covariant nonlocal interactions. For applications to compact stars, we impose conditions of electric and color charge neutrality as well as beta equilibrium and construct a phase transition to the hadronic matter phase described within the Dirac-Brueckner-Hartree-Fock (DBHF) approach. We obtain mass-radius relations for hybrid star configurations which fulfill modern observational constraints, including compact star masses above 2 M_sun.