Spinodal Instabilities in Asymmetric Nuclear Matter Based on Realistic $NN$ Interactions

TL;DR

This paper uses a density-dependent relativistic mean-field model to study spinodal instabilities in asymmetric nuclear matter, revealing a larger instability region and lower critical temperature compared to previous microscopic models.

Contribution

It introduces a relativistic mean-field approach calibrated to nucleon self-energies to analyze spinodal instabilities in asymmetric nuclear matter at finite temperatures.

Findings

The spinodal region is larger than in phenomenological models.

The critical temperature for instabilities is lower than in non-relativistic approaches.

Instabilities are concentrated around isospin symmetric nuclear matter.

Abstract

A density dependent relativistic mean-field model is determined to reproduce the components of the nucleon self-energy at low densities. This model is used to investigate spinodal instabilities in isospin asymmetric nuclear matter at finite temperatures. The inhomogeneous density distributions in the spinodal region are investigated through calculations in a cubic Wigner-Seitz cell. Compared to results obtained in phenomenological calculations the spinodal region is large, i.e. the spinodal region at zero temperature can reach densities above 0.12 fm$^{-3}$. The predicted spinodal region is concentrated around isospin symmetric nuclear matter and the critical temperature is considerably lower than in the previous microscopic based investigation within a non-relativistic Brueckner-Hartree-Fock approach.