High-density Skyrmion matter and Neutron Stars

TL;DR

This paper models neutron star matter using skyrmions in a mesonic background, showing that such matter can explain observed massive neutron stars and suggesting it is stiffer than traditional models at high densities.

Contribution

It introduces a skyrmion-based dense matter model with chiral symmetry breaking and scale effects, aligning neutron star properties with recent observational data.

Findings

Neutron star masses up to 1.7 solar masses are consistent with the model.

Predicted neutron star radii are in the range 12-14 km.

The model suggests matter at high density is stiffer than previous microscopic models.

Abstract

We examine neutron star properties based on a model of dense matter composed of B=1 skyrmions immersed in a mesonic mean field background. The model realizes spontaneous chiral symmetry breaking non-linearly and incorporates scale-breaking of QCD through a dilaton VEV that also affects the mean fields. Quartic self-interactions among the vector mesons are introduced on grounds of naturalness in the corresponding effective field theory. Within a plausible range of the quartic couplings, the model generates neutron star masses and radii that are consistent with a preponderance of observational constraints, including recent ones that point to the existence of relatively massive neutron stars with mass M 1.7 Msun and radius R (12-14) km. If the existence of neutron stars with such dimensions is confirmed, matter at supra-nuclear density is stiffer than extrapolations of most microscopic models suggest.