Fitting Skyrme functionals using linear response theory

TL;DR

This paper introduces a new fitting protocol for Skyrme functionals that leverages linear response theory to ensure stability in finite nuclei by constraining the functional in symmetric nuclear matter, preventing instabilities.

Contribution

It presents a novel fitting method that incorporates linear response constraints to produce stable Skyrme functionals, improving upon previous models.

Findings

Developed a new Skyrme functional free from instabilities.

Established a correlation between infinite matter instabilities and finite nuclei stability.

Provided a parameter set for a stable Skyrme functional with central and spin-orbit parts.

Abstract

Recently, it has been recently shown that the linear response theory in symmetric nuclear matter can be used as a tool to detect finite size instabilities for different Skyrme functionals. In particular it has been shown that there is a correlation between the density at which instabilities occur in infinite matter and the instabilities in finite nuclei. In this article we present a new fitting protocol that uses this correlation to add new additional constraint in Symmetric Infinite Nuclear Matter in order to ensure the stability of finite nuclei against matter fluctuation in all spin and isospin channels. As an application, we give the parameters set for a new Skyrme functional which includes central and spin-orbit parts and which is free from instabilities by construction.