Dense Nuclear Matter with Baryon Overlap

TL;DR

This paper explores how incorporating short-distance physics related to baryon overlap into the quark-meson coupling model affects the equation of state, enabling neutron stars with masses exceeding 2.1 solar masses even with hyperons.

Contribution

It introduces a new physics component proportional to baryon overlap into the equation of state, maintaining nuclear matter properties and supporting massive neutron stars.

Findings

Supports neutron stars >2.1 solar masses with hyperons

Maintains properties of symmetric nuclear matter at saturation

Incorporates short-distance physics into the EOS

Abstract

The possibility of new short-distance physics applicable inside the cores of NS is incorporated into the equation of state generated by the quark-meson coupling model. The contribution of this new physics to the energy density is taken to be proportional to the amount of overlap between the quark cores of the baryons involved. With no change to the properties of symmetric nuclear matter at saturation density, including an incompressibility compatible with data on giant monopole resonances, one can sustain neutron stars with a maximum mass $M_{max}>2.1$ M$_\odot$, even when hyperons are included.