New relativistic effective interaction for finite nuclei, infinite nuclear matter and neutron stars

TL;DR

This paper introduces a new relativistic force, IOPB-I, for modeling finite nuclei, nuclear matter, and neutron stars, showing good agreement with experimental data and astrophysical observations.

Contribution

The paper develops and applies a new relativistic effective interaction, IOPB-I, to accurately describe nuclear properties and neutron star characteristics, including shell gaps and equation of state.

Findings

Shell gaps at N=172, 184, 198 indicate magic numbers.

Neutron star maximum mass is 2.15 solar masses.

Neutron star radius for 1.4 solar masses is 13.242 km.

Abstract

We carry out the study for finite nuclei, infinite nuclear matter and neutron star properties with the newly developed relativistic force named as the Institute Of Physics Bhubaneswar-I(IOPB-I). Using this force, we calculate the binding energies, charge radii and neutron skin thickness for some selected nuclei. From the ground state properties of superheavy element i.e. Z=120, it is noticed that considerable shell gaps appear at neutron numbers N=172, 184 and 198, showing the magicity of these numbers. The low density behavior of the equation of state for pure neutron matter is compatible with other microscopic models. Along with the nuclear symmetry energy, its slope and curvature parameters at the saturation density are consistent with those extracted from various experimental data. We calculate the neutron star properties with the equation of state composed of nucleons and leptons in $\it beta-equilibrium$ which are in good agreement with the X-ray observations by Steiner and N\"{a}ttil\"{a}. We find that the maximum mass of the neutron star to be 2.15$M_{\odot}$ and stellar radius 11.936 km . Moreover, the radius and tidal deformability of a {\it canonical} neutron star mass 1.4$M_\odot$ come out to be 13.242 km and 3.910$\times$10$^{36}$ g cm$^2$ s$^2$ respectively within this parameter set.