Nuclear symmetry energy with mesonic cross-couplings in the effective chiral model

TL;DR

This paper extends the effective chiral model by incorporating mesonic cross-couplings, which improves the description of nuclear symmetry energy and neutron star properties, aligning well with experimental and observational data.

Contribution

Introduction of mesonic cross-couplings into the effective chiral model to better describe nuclear symmetry energy and neutron star characteristics.

Findings

Nuclear symmetry energy matches experimental data.

Neutron star maximum mass aligns with observations.

Equation of state agrees with microscopic models.

Abstract

The effective chiral model is extended by introducing the contributions from the cross-couplings between isovector and isoscalar mesons. These cross-couplings are found to be instrumental in improving the density content of the nuclear symmetry energy. The nuclear symmetry energy as well as its slope and curvature parameters at the saturation density are in harmony with those deduced from a diverse set of experimental data. The equation of state for pure neutron matter at sub-saturation densities is also in accordance with the ones obtained from different microscopic models. The maximum mass of neutron star is consistent with the measurement and the radius at the canonical mass of the neutron star is within the empirical bounds.