Non-empirical pairing functional

TL;DR

This paper presents the first systematic finite-nucleus calculations using a non-empirical pairing functional derived from low-momentum interactions, comparing results with empirical functionals and suggesting modifications for improved accuracy.

Contribution

It introduces a novel non-empirical pairing functional based on low-momentum interactions and systematically characterizes pairing correlations in finite nuclei.

Findings

Neutron-neutron and proton-proton pairing correlations are systematically characterized.

Predictions are compared with empirical local functionals, revealing insights into their differences.

A modification to the isovector density dependence of empirical functionals is proposed.

Abstract

The present contribution reports the first systematic finite-nucleus calculations performed using the Energy Density Functional method and a non-empirical pairing functional derived from low-momentum interactions. As a first step, the effects of Coulomb and the three-body force are omitted while only the bare two-nucleon interaction at lowest order is considered. To cope with the finite-range and non-locality of the bare nuclear interaction, the 1S0 channel of Vlowk is mapped onto a convenient operator form. For the first time, neutron-neutron and proton-proton pairing correlations generated in finite nuclei by the direct term of the two-nucleon interaction are characterized in a systematic manner. Eventually, such predictions are compared to those obtained from empirical local functionals derived from density-dependent zero range interactions. The characteristics of the latter are analyzed in view of that comparison and a specific modification of their isovector density dependence is suggested to accommodate Coulomb effects and the isovector trend of neutron gaps at the same time.