Towards a microscopic description of nucleus-nucleus collisions

TL;DR

This paper develops a microscopic optical potential approach for nucleus-nucleus elastic collisions using chiral interactions and ab initio nuclear densities, successfully matching experimental cross sections at certain energies and momentum transfers.

Contribution

It introduces a first-order multiple-scattering microscopic model with chiral interactions and ab initio densities for nucleus-nucleus collisions, providing improved theoretical predictions.

Findings

Good agreement with experimental data for momentum transfer up to 1.0 fm$^{-1}$

The model accurately predicts cross sections at energies 100-300 MeV

Higher momentum transfer requires adjustments to the imaginary part of the potential

Abstract

We present the first results of a comprehensive microscopic approach to describe nucleus-nucleus elastic collisions by means of an optical potential derived at first order in multiple-scattering theory and computed by folding the projectile and target nuclear densities with the nucleon-nucleon $t$ matrix, which describes the interaction between each nucleon of the projectile and each nucleon of the target. Chiral interactions are consistently used in the calculation of the $t$ matrix and of the nonlocal nuclear densities, which are computed within the ab initio no-core shell model. Cross sections calculated for $\alpha$ collisions on $^{12}$C and $^{16}$O at projectile energies in the range 100-300 MeV are presented and compared with available data. For momentum transfer $q$ up to about $1.0$ fm$^{-1}$ our results are in good agreement with the experimental data, whereas for higher momenta a reduction of the imaginary contributions is needed.