Correlated structure of nuclear symmetry energy from covariant nucleon self-energy

TL;DR

This paper investigates the structure of nuclear symmetry energy and its density dependence using covariant density functional theory, revealing fundamental correlations and the impact of various interaction channels on these relationships.

Contribution

It introduces a covariant framework to decompose symmetry energy parameters and explores their correlations, highlighting the effects of isovector scalar channels and second-order self-energies.

Findings

Fundamental correlation between symmetry energy $J$ and slope $L$ established.

Isovector scalar channel and second-order self-energies affect the $J$-$L$ correlation.

Linear relation between Landau mass and Dirac mass demonstrated.

Abstract

Based on the Hugenholtz-Van Hove theorem, the symmetry energy $J$ and its density slope parameter $L$ are decomposed in terms of the nucleon self-energies within the covariant density functional (CDF) theory. It is found that two structural connections between the different ingredients of $J$ and $L$ construct the fundamental correlation between $L$ and $J$ in the relativistic covariant framework, while the additional contribution from the isovector scalar channel of nucleon-nucleon interaction and those from the second-order symmetry self-energies lead to a deviation, especially the latter limits severely its correlation coefficient and confidence level. In addition, the relationship between the Landau mass $M_L^*$ and the Dirac mass $M_D^*$ is approximated to a reliable linear correlation, which is demonstrate to be sensitive to the momentum dependence of the nucleon self-energies.