Response of asymmetric nuclear matter studied with a finite number of particles

TL;DR

This paper explores the properties and response of asymmetric nuclear matter to external fields using an extended density functional theory approach, highlighting finite-size effects and non-monotonic isovector response behavior.

Contribution

It extends a finite-nucleon-number technique to isospin-asymmetric matter, enabling detailed analysis of densities and response functions in different isospin channels.

Findings

Finite-size effects are significant and compared with RPA predictions.

Non-monotonic behavior observed in the isovector response function.

External fields influence densities and response functions in asymmetric nuclear matter.

Abstract

We investigate the ground-state properties of asymmetric nuclear matter and its response to a static perturbation using the density functional theory framework. Our method, which extends the finite-nucleon-number technique of arXiv:2211.07986 to the case of isospin-asymmetric matter, allows to study the impact of external isoscalar and isovector fields on the system. In particular, the densities and static response functions in the different isospin channels, and as a function of isospin asymmetry, are evaluated. Finite-size effects are discussed by comparing with Random Phase Approximation predictions in the thermodynamic limit. A peculiar non-monotonic behavior of the isovector response function is analyzed.