A new equation of state for neutron star matter with nuclei in the crust and hyperons in the core

TL;DR

This paper develops a comprehensive equation of state for neutron star matter, incorporating nuclei in the crust and hyperons in the core, consistent with recent pulsar mass observations.

Contribution

It introduces a new EOS model using the chiral quark-meson coupling within a relativistic Hartree-Fock framework, including hyperons and nuclei effects.

Findings

Maximum neutron star mass of 1.95 solar masses

EOS consistent with observed massive pulsars

Includes hyperons and nuclear nuclei in a unified model

Abstract

The equation of state for neutron stars in a wide-density range at zero temperature is constructed. The chiral quark-meson coupling model within relativistic Hartree-Fock approximation is adopted for uniform nuclear matter. The coupling constants are determined so as to reproduce the experimental data of atomic nuclei and hypernuclei. In the crust region, nuclei are taken into account within the Thomas-Fermi calculation. All octet baryons are considered in the core region, while only $\Xi^{-}$ appears in neutron stars. The resultant maximum mass of neutron stars is $1.95M_\odot$, which is consistent with the constraint from the recently observed massive pulsar, PSR J1614-2230.