Hybrid Stars in an SU(3) Parity Doublet Model

TL;DR

This paper extends an SU(3) parity model including quarks to study neutron stars, successfully reproducing QCD features, describing dense matter composition, and satisfying observational constraints.

Contribution

It introduces an extended SU(3) parity model with quark degrees of freedom for neutron star analysis, capturing chiral symmetry restoration and deconfinement transitions.

Findings

Chiral symmetry restoration occurs inside neutron stars.

Quark degrees of freedom appear during the transition to deconfined matter.

Model predictions align with observational constraints on neutron star properties.

Abstract

We apply an extended version of the SU(3) parity model, containing quark degrees of freedom, to study neutron stars. The model successfully reproduces the main thermodynamic features of QCD which allows us to describe the composition of dense matter. Chiral symmetry restoration is realized inside the star and the chiral partners of the baryons appear, their masses becoming degenerate. Furthermore, quark degrees of freedom appear in a transition to a deconfined state. Performing an investigation of the macroscopic properties of neutron stars, we show that observational constraints, like mass and thermal evolution, are satisfied and new predictions can be made.