Temperature dependence of single-particle properties in nuclear matter

TL;DR

This paper investigates how temperature and density affect single-particle properties in hot nuclear matter using Brueckner theory with realistic interactions, highlighting the role of three-body forces and correlations.

Contribution

It provides a detailed analysis of temperature and density effects on single-particle potentials and effective mass, emphasizing the impact of three-body forces in nuclear matter.

Findings

Ground state correlations induce a significant repulsive contribution at low momenta.

Increasing temperature reduces the effects of correlations on the potential.

Three-body forces alter the temperature dependence of the potential at high densities.

Abstract

The single-nucleon potential in hot nuclear matter is investigated in the framework of the Brueckner theory by adopting the realistic Argonne V18 or Nijmegen 93 two-body nucleon-nucleon interaction supplemented by a microscopic three-body force. The rearrangement contribution to the single-particle potential induced by the ground state correlations is calculated in terms of the hole-line expansion of the mass operator and provides a significant repulsive contribution in the low-momentum region around and below the Fermi surface. Increasing temperature leads to a reduction of the effect, while increasing density makes it become stronger. The three-body force suppresses somewhat the ground state correlations due to its strong short-range repulsion, increasing with density. Inclusion of the three-body force contribution results in a quite different temperature dependence of the single-particle potential at high enough densities as compared to that adopting the pure two-body force. The effects of three-body force and ground state correlations on the nucleon effective mass are also discussed.