Thermodynamic and Transport properties of hot asymmetric nuclear matter within a chiral SU(3) model

TL;DR

This paper explores the thermodynamic and transport properties of hot asymmetric nuclear matter using a chiral SU(3) model, revealing significant medium modifications and effects of isospin asymmetry relevant for heavy-ion collision experiments.

Contribution

It introduces a detailed analysis of shear viscosity and thermal conductivity in hot nuclear matter within a chiral SU(3) framework, including medium and isospin asymmetry effects.

Findings

Shear viscosity is lower than in free nucleon gas.

Thermal conductivity is higher than in free nucleon gas.

The shear viscosity to entropy density ratio decreases with density and temperature.

Abstract

We investigate the thermodynamic and transport properties in hot nuclear matter accounting for the medium modifications of the nucleons within a chiral SU(3) model including effects from isospin asymmetry. Using the relaxation time approximation, the transport coefficients of the shear viscosity and thermal conductivity are studied. The shear viscosity, $\eta$, calculated within the chiral SU(3) model is observed to be smaller than the values calculated for free nucleon gas, whereas the thermal conductivity $\kappa$ is appreciably larger as compared to the free nucleon gas. The shear viscosity coefficient to entropy density ratio, $\eta/s$, drops with increasing baryon density which becomes more pronounced at higher temperatures in the chiral SU(3) model as compared to the case of a free nucleon gas. The effect due to isospin asymmetry on the coefficient of shear viscosity turns out to be marginal. However, in the chiral SU(3) model, in presence of isospin asymmetry, the coefficient of thermal conductivity has an appreciably higher value as compared to the one for symmetric nuclear matter. The present study of the thermodynamic as well as transport properties in hot nuclear matter is of relevance for relativistic heavy-ion collisions with different initial isospin asymmetry, in particular for the compressed baryonic matter (CBM) experiment at the FAIR facility at GSI.