Nonlocality parameters of microscopic optical potentials from Skyrme-based nuclear structure models at low energies

TL;DR

This study derives nonlocality parameters for nucleon-nucleus interactions from microscopic optical potentials based on Skyrme nuclear models, revealing their dependence on energy, position, and target nucleus without adjustable parameters.

Contribution

It provides a parameter-free, microscopic determination of nonlocality parameters in optical potentials using Skyrme models at low energies, highlighting their spatial and nuclear dependence.

Findings

Nonlocality parameter $eta$ varies with energy, position, and nucleus.

At energies below 30 MeV, $eta$ ranges from 0.8 to 1.2 fm.

Interior $eta$ is smaller for $^{16}$O and similar in surface and interior for heavier nuclei.

Abstract

We investigate the non-locality parameters $ \beta $ in nucleon-nucleus interactions for $ ^{16}\mathrm{O} $, $ ^{40}\mathrm{Ca} $, $ ^{48}\mathrm{Ca} $, and $ ^{208}\mathrm{Pb} $ using a microscopic optical potential (MOP) derived from nuclear structure models based on Skyrme self-consistent mean-field calculations at low incident energies. No ad hoc adjusted parameters were employed in the present calculations. The analysis reveals that the non-locality parameter exhibits a clear dependence on the radial position within the nucleus, the incident nucleon energy, and the choice of target nucleus. At incident energies below $30$ MeV, the $ \beta $ lies between $0.8$ fm and $1.2$ fm for all considered targets. For the light nucleus $^{16}\mathrm{O}$, the non-locality parameter in the interior is smaller than that on the surface, whereas for medium and heavy nuclei $( ^{40}\mathrm{Ca} $, $ ^{48}\mathrm{Ca} $, and $ ^{208}\mathrm{Pb} $ ), the values are comparable in both regions.