Finite- to zero-range relativistic mean-field interactions

TL;DR

This paper explores the connection between finite-range meson-exchange and zero-range point-coupling models in relativistic nuclear physics, constructing and analyzing a family of effective interactions to understand their relationship and constraints.

Contribution

It introduces a method to derive zero-range interactions from finite-range models by varying the sigma-meson mass, providing insights into their equivalence and parameter constraints.

Findings

Zero-range and finite-range models can be related through sigma-meson mass variation.

Parameters fitted to nuclear matter and finite nuclei properties show consistent results.

Constraints on point-coupling parameters are discussed based on nuclear matter and finite nuclei data.

Abstract

We study the relation between the finite-range (meson-exchange) and zero-range (point-coupling) representations of effective nuclear interactions in the relativistic mean-field framework. Starting from the phenomenological interaction DD-ME2 with density-dependent meson-nucleon couplings, we construct a family of point-coupling effective interactions for different values of the strength parameter of the isoscalar-scalar derivative term. In the meson-exchange picture this corresponds to different values of the $\sigma$-meson mass. The parameters of the isoscalar-scalar and isovector-vector channels of the point-coupling interactions are adjusted to nuclear matter and ground-state properties of finite nuclei. By comparing results for infinite and semi-infinite nuclear matter, ground-state masses, charge radii, and collective excitations, we discuss constraints on the parameters of phenomenological point-coupling relativistic effective interaction.