Lee-Yang-inspired functional including contributions to fourth order in effective field theory

TL;DR

This paper extends the ELYO energy density functional by incorporating fourth-order EFT terms, improving neutron effective mass predictions and offering nuanced insights into neutron-drop energies under different harmonic trap conditions.

Contribution

It introduces a new extension of the ELYO functional including fourth-order EFT contributions, enhancing the accuracy of neutron effective mass calculations.

Findings

Neutron effective mass aligns better with ab-initio estimates.

Neutron-drop energy description slightly degrades at higher trap frequency.

Improved agreement with ab-initio data at lower trap frequency.

Abstract

In the last years, a new family of energy density functionals directly inspired by effective field theory (EFT) has been developed, among which the ELYO (extended Lee-Yang Orsay) functional. In this paper, a new extension of ELYO that includes the recently calculated fourth-order EFT terms is presented. Compared to the previous version, the description of neutron-drop energies slightly degrades for a harmonic trap $\hbar\omega =10$ MeV -- yet remaining reasonable -- , but improves for $\hbar\omega =5$ MeV. Furthermore, the obtained neutron effective mass agrees significantly better with \textit{ab-initio} estimates.