Deconfinement phase transition in hybrid neutron stars from the Brueckner theory with three-body forces and a quark model with chiral mass scaling

TL;DR

This paper investigates the phase transition from nuclear to quark matter in neutron stars using a chiral mass scaling model for quark confinement and Brueckner theory for nuclear matter, revealing mixed phases near saturation density.

Contribution

It introduces a density-dependent quark mass model based on chiral condensates and combines it with Brueckner theory to study deconfinement in neutron stars, offering a novel approach to phase transition analysis.

Findings

Mixed phase occurs near nuclear saturation density.

Pure quark matter appears at about 5 times saturation density.

Transition models are compatible with observed low-mass neutron stars.

Abstract

We study the properties of strange quark matter in equilibrium with normal nuclear matter. Instead of using the conventional bag model in quark sector, we achieve the confinement by a density-dependent quark mass derived from in-medium chiral condensates. In nuclear matter, we adopt the equation of state from the Brueckner-Bethe-Goldstone approach with three-body forces. It is found that the mixed phase can occur, for a reasonable confinement parameter, near the normal nuclear saturation density, and goes over into pure quark matter at about 5 times the saturation. The onset of mixed and quark phases is compatible with the observed class of low-mass neutron stars, but it hinders the occurrence of kaon condensation.