Implications of PSR J1614-2230 for NJL hybrid star

TL;DR

This paper investigates the impact of recent neutron star mass measurements on the existence of exotic matter in their cores, using hybrid star models with various equations of state.

Contribution

It provides an extensive analysis of hybrid star masses employing multiple hadronic EoS parametrizations and a three-flavor NJL model with complex interactions.

Findings

Maximum neutron star mass constraints from PSR J1614-2230 are examined.

Hybrid star models can accommodate the observed high masses.

The study explores the role of exotic matter in neutron star cores.

Abstract

The recent determination of the mass of the pulsar PSR J1614-2230 with $1.97 \pm 0.04 M_\odot$ by \cite{Demorest}, renewed the discussions about the possibility of exotic matter being present at the core of neutron stars. Since the description of matter at densities beyond nuclear saturation is model dependent, several works have explored different aspects of the fact that the maximum neutron star mass implied by any equation of state (EoS) must exceed the mass of PSR J1614-2230. In this article we present an extensive study of hybrid star masses using several parametrizations of a relativistic mean-field hadronic EoS together with a typical three-flavor NJL model with scalar, vector and 't Hooft interactions as realized.