Constraining nuclear matter parameters and neutron star observables using PREX-2 and NICER data

TL;DR

This paper constrains nuclear matter parameters using PREX-2 and NICER data, analyzes correlations among parameters, and assesses neutron star properties, finding that NICER data narrows radius estimates but leaves some uncertainties.

Contribution

It provides updated constraints on nuclear matter parameters and neutron star radii by combining recent PREX-2 and NICER observational data.

Findings

Strong correlations between nuclear matter parameters identified.

Neutron star radii are more tightly constrained by recent NICER data.

Results are consistent with observed pulsars, with some exceptions.

Abstract

We try to constraints some of the nuclear matter parameters such as symmetry energy ($J$) and its slope ($L$) from the recent inferred data of the PREX-2. Other nuclear matter parameters are adopted from {\bf [Phys. Rev. C 85 035201 (2012), Phys. Rev. C 90 055203 (2014)]} papers and the linear correlation among them are checked by using the Pearson's formula. We find the correlation between $J-L$, $K_\tau-J$ and $K_\tau-L$ with coefficients 0.85, 0.81 and 0.76 respectively. The neutron star properties such as mass and radius are calculated with 50 unified equation of states. The results are consistent with recently observed pulsars and NICER data except few exceptions. From the radii constraints, we find that the new NICER data allows a narrow radius range contrary to a large range of PREX-2 and the old NICER data leaving us an inconclusive determination of the neutron star radius.