Ab initio Folding Potentials for Nucleon-Nucleus Scattering based on NCSM One-Body Densities

TL;DR

This paper develops a microscopic optical potential for nucleon-nucleus scattering using ab initio nuclear densities and chiral NN interactions, accurately predicting scattering observables for light nuclei at intermediate energies.

Contribution

It introduces a fully consistent folding model combining NCSM-derived densities with chiral NN interactions for scattering calculations.

Findings

Accurately reproduces scattering data up to 60 degrees.

Demonstrates the effectiveness of ab initio densities in optical potential calculations.

Validates the use of chiral NN interactions in scattering models.

Abstract

Calculating microscopic optical potentials for elastic nucleon-nucleus scattering has already led to large body of work in the past. For folding first-order calculations the nucleon-nucleon (NN) interaction and the one-body density of the nucleus were taken as input to rigorous calculations in a spectator expansion of the multiple scattering series. Based on the Watson expansion of the multiple scattering series we employ a nonlocal translationally invariant nuclear density derived from a chiral next-to-next-to-leading order (NNLO) and the very same interaction for consistent full-folding calculation of the effective (optical) potential for nucleon-nucleus scattering for light nuclei. We calculate scattering observables, such as total, reaction, and differential cross sections as well as the analyzing power and the spin-rotation parameter, for elastic scattering of protons and neutrons from $^4$He, $^{6}$He, $^{12}$C, and $^{16}$O, in the energy regime between 100 and 200~MeV projectile kinetic energy, and compare to available data. Our calculations show that the effective nucleon-nucleus potential obtained from the first-order term in the spectator expansion of the multiple scattering expansion describes experiments very well to about 60 degrees in the center-of-mass frame, which coincides roughly with the validity of the NNLO chiral interaction used to calculate both the NN amplitudes and the one-body nuclear density.