The properties of the neutron star PSR J0348+0432

TL;DR

This paper models the properties of the massive neutron star PSR J0348+0432 using relativistic mean field theory, revealing differences in internal composition, density, pressure, radius, and redshift compared to typical neutron stars.

Contribution

It provides a detailed theoretical analysis of PSR J0348+0432's properties, including hyperon effects and internal structure, which are novel insights into such massive neutron stars.

Findings

Central energy density and pressure are significantly higher in PSR J0348+0432.

Presence of five baryon types in PSR J0348+0432 versus three in typical neutron stars.

PSR J0348+0432 has a smaller radius but higher gravitational redshift.

Abstract

The properties of the massive neutron star PSR J0348+0432 is calculated in the framework of the relativistic mean field theory by choosing the suitable hyperon coupling constants. It is found that the central energy density $\epsilon_{c}$ and the central pressure $p_{c}$ of the massive neutron star PSR J0348+0432 respectively are 1.5 times larger and 3.6 times larger than those of the canonical mass neutron star. It is also found that in the neutron star PSR J0348+0432 there are five kinds of baryons appearing: n, p, $\Lambda$, $\Xi^{-}$ and $\Xi^{0}$ but in the canonical mass neutron star there are only three kinds of particles appearing: n, p and $\Lambda$. In our models, the positive well depth $U_{\Sigma}^{(N)}$ will restrict the production of the hyperons $\Sigma^{-}$, $\Sigma^{0}$ and $\Sigma^{+}$ and therefore either in the neutron star PSR J0348+0432 or in the canonical mass neutron star the hyperons $\Sigma^{-}$, $\Sigma^{0}$ and $\Sigma^{+}$ all do not appear. In addition, our results also show that the radius $R$ of the massive neutron star PSR J0348+0432 is less than that of the canonical mass neutron star while the gravitational redshift of the former is larger than that of the latter.