Neutron-skin thickness of finite nuclei in relativistic mean-field models with chiral limits

TL;DR

This paper investigates how chiral symmetry restoration influences neutron skin thickness in finite nuclei using relativistic mean-field models, successfully aligning with experimental data and revealing a reduced neutron skin compared to traditional models.

Contribution

The study introduces relativistic mean-field models incorporating chiral symmetry effects, providing improved predictions for neutron skin thickness and nuclear structure properties.

Findings

Models predict neutron skin thickness of 0.17-0.21 fm for ^{208}Pb.

Chiral symmetry restoration leads to softer symmetry energy.

Models align with experimental constraints on nuclear matter.

Abstract

We study several structure properties of finite nuclei using relativistic mean-field Lagrangians constructed according to the Brown-Rho scaling due to the chiral symmetry restoration at high densities. The models are consistent with current experimental constraints for the equations of state of symmetric matter at both normal and supra-normal densities and of asymmetric matter at sub-saturation densities. It is shown that these models can successfully describe the binding energies and charge radii of finite nuclei. Compared to calculations with usual relativistic mean-field models, these models give a reduced thickness of neutron skin in ^{208}Pb between 0.17 fm and 0.21 fm. The reduction of the predicted neutron skin thickness is found to be due to not only the softening of the symmetry energy but also the scaling property of $\rho $ meson required by the partial restoration of chiral symmetry.