Spin and spin-isospin instabilities in asymmetric nuclear matter at zero and finite temperatures using Skyrme functionals

TL;DR

This paper investigates spin and spin-isospin instabilities in asymmetric nuclear matter using Skyrme functionals, identifies their origins, and proposes a method to eliminate these instabilities for more reliable nuclear matter modeling.

Contribution

It revisits the origin of instabilities in Skyrme functionals and introduces a simple prescription to remove them, improving the stability of nuclear matter calculations.

Findings

Identified the source of spurious instabilities in Skyrme functionals.

Proposed a prescription to eliminate spin and spin-isospin instabilities.

Reexamined the stability of various Skyrme parametrizations.

Abstract

Self-consistent mean field methods based on phenomenological Skyrme effective interactions are known to exhibit spurious spin and spin-isospin instabilities both at zero and finite temperatures when applied to homogeneous nuclear matter at the densities encountered in neutron stars and in supernova cores. The origin of these instabilities is revisited in the framework of the nuclear energy density functional theory and a simple prescription is proposed to remove them. The stability of several Skyrme parametrizations is reexamined.