# Warm unstable asymmetric nuclear matter: critical properties and the density dependence of the symmetry energy

## TL;DR

This paper investigates the critical properties and spinodal instabilities of warm asymmetric nuclear matter using various relativistic mean-field models, highlighting the sensitivity of critical parameters to the symmetry energy slope and temperature.

## Contribution

It provides a detailed analysis of how the density dependence of the symmetry energy influences critical properties and instabilities in warm asymmetric nuclear matter, using multiple RMF model families.

## Key findings

- Critical densities and proton fractions depend on the symmetry energy slope at low temperatures.
- The spread in critical proton fraction increases near the critical temperature.
- Distillation effects are affected by the density dependence of symmetry energy at low temperatures.

## Abstract

The spinodal instabilities in hot asymmetric nuclear matter and some important critical parameters derived thereof are studied using six different families of relativistic mean-field (RMF) models. The slopes of the symmetry energy coefficient vary over a wide range within each family. The critical densities and proton fractions are more sensitive to the symmetry energy slope parameter at temperatures much below its critical value ($T_c\sim$14-16 MeV). The spread in the critical proton fraction at a given symmetry energy slope parameter is noticeably larger near $T_c$, indicating that the warm equation of state of asymmetric nuclear matter at sub-saturation densities is not sufficiently constrained. The distillation effects are sensitive to the density dependence of the symmetry energy at low temperatures which tend to wash out with increasing temperature.