Perturbed nuclear matter studied within Density Functional Theory with a finite number of particles

TL;DR

This paper develops a Density Functional Theory approach using a finite particle box to simulate infinite nuclear matter, analyzing its response to external perturbations and advancing ab initio-based nuclear energy density functionals.

Contribution

It introduces a novel finite-particle DFT method with detailed formalism and implementation for nuclear matter, aiding the development of ab initio-based energy density functionals.

Findings

Analyzed static response of nuclear matter to external potentials

Assessed impact of perturbations on energies and densities

Provided a framework for constraining EDF surface terms

Abstract

Nuclear matter is studied within the Density Functional Theory (DFT) framework. Our method employs a finite number of nucleons in a box subject to periodic boundary conditions, in order to simulate infinite matter and study its response to an external static potential. We detail both the theoretical formalism and its computational implementation for pure neutron matter and symmetric nuclear matter with Skyrme-like Energy Density Functionals (EDFs). The implementation of spin-orbit, in particular, is carefully discussed. Our method is applied to the problem of the static response of nuclear matter and the impact of the perturbation on the energies, densities and level structure of the system is investigated. Our work is a crucial step in our program of ab initio-based nuclear EDFs [Phys. Rev. C 104, 024315 (2021)] as it paves the way towards the goal of constraining the EDF surface terms on ab initio calculations.