Functional renormalization group study of nuclear and neutron matter

TL;DR

This paper uses the functional renormalization group to study nuclear and neutron matter, revealing no chiral restoration up to high temperatures and densities, and exploring implications for neutron stars.

Contribution

It introduces a chiral nucleon model with fluctuation effects beyond mean-field, providing new insights into phase transitions and neutron star constraints.

Findings

No chiral restoration up to 100 MeV and three times nuclear density

Detailed analysis of the liquid-gas phase transition

Extension to asymmetric matter and neutron star constraints

Abstract

A chiral model based on nucleons interacting via boson exchange is investigated. Fluctuation effects are included consistently beyond the mean-field approximation in the framework of the functional renormalization group. The liquid-gas phase transition of symmetric nuclear matter is studied in detail. No sign of a chiral restoration transition is found up to temperatures of about 100 MeV and densities of at least three times the density of normal nuclear matter. Moreover, the model is extended to asymmetric nuclear matter and the constraints from neutron star observations are discussed.