Variational Theory of Hot Nucleon Matter II : Spin-Isospin Correlations and Equation of State of Nuclear and Neutron Matter

TL;DR

This paper extends a variational theory for fermions to finite temperatures, analyzing spin-isospin correlations and deriving the equation of state for hot dense nuclear and neutron matter, relevant for astrophysical applications.

Contribution

It generalizes the zero-temperature many-body technique to finite temperatures, enabling practical calculations of hot dense nuclear matter with detailed spin-isospin correlation analysis.

Findings

Equation of state for temperatures <30 MeV and densities <3 times saturation density.

Analysis of neutral pion condensation and isovector spin sum rules.

Discussion of nucleon effective mass behavior in medium.

Abstract

We apply the variational theory for fermions at finite temperature and high density, developed in an earlier paper, to symmetric nuclear matter and pure neutron matter. This extension generalizes to finite temperatures, the many body technique used in the construction of the zero temperature Akmal-Pandharipande-Ravenhall equation of state. We discuss how the formalism can be used for practical calculations of hot dense matter. Neutral pion condensation along with the associated isovector spin longitudinal sum rule is analyzed. The equation of state is calculated for temperatures less than 30 MeV and densities less than three times the saturation density of nuclear matter. The behavior of the nucleon effective mass in medium is also discussed.