In medium T-matrix for nuclear matter with three-body forces - binding energy and single particle properties

TL;DR

This paper investigates nuclear matter properties using an in-medium T-matrix approach with three-body forces, revealing a soft equation of state and notable effects on spectral functions at high densities.

Contribution

It introduces a method to include three-body forces in the in-medium T-matrix calculations and analyzes their impact on nuclear matter properties and single-particle spectral functions.

Findings

Soft equation of state in symmetric nuclear matter.

Large symmetry energy at saturation density.

Spectral functions broaden at high densities for symmetric matter.

Abstract

We present spectral calculations of nuclear matter properties including three-body forces. Within the in-medium T-matrix approach, implemented with the CD-Bonn and Nijmegen potentials plus the three-nucleon Urbana interaction, we compute the energy per particle in symmetric and neutron matter. The three-body forces are included via an effective density dependent two-body force in the in-medium T-matrix equations. After fine tuning the parameters of the three-body force to reproduce the phenomenological saturation point in symmetric nuclear matter, we calculate the incompressibility and the energy per particle in neutron matter. We find a soft equation of state in symmetric nuclear matter but a relatively large value of the symmetry energy. We study the the influence of the three-body forces on the single-particle properties. For symmetric matter the spectral function is broadened at all momenta and all densities, while an opposite effect is found for the case of neutrons only. Noticeable modification of the spectral functions are realized only for densities above the saturation density. The modifications of the self-energy and the effective mass are not very large and appear to be strongly suppressed above the Fermi momentum.