Faddeev-type calculation of three-body nuclear reactions including core excitation

TL;DR

This paper develops an exact Faddeev-type framework to include core excitation in three-body nuclear reaction calculations, improving the accuracy of modeling reactions involving nuclei like 10Be and 24Mg.

Contribution

It introduces a novel method to incorporate core excitation into three-body nuclear reaction calculations using Faddeev-type equations, addressing a gap in previous models.

Findings

Core excitation significantly affects reaction outcomes.

Improved agreement with experimental data when including core excitation.

Spectroscopic factors may not be reliably extracted from transfer reactions.

Abstract

The core excitation, being an important reaction mechanism, so far is not properly included in most calculations of three-body nuclear reactions. We aim to include the excitation of the core nucleus using an exact Faddeev-type framework for nuclear reactions in the three-body (core + neutron + proton) system. We employ Alt, Grassberger, and Sandhas (AGS) integral equations for the three-particle transition operators and solve them in the momentum-space framework. The Coulomb interaction is included via the method of screening and renormalization. We calculate elastic, inelastic, and transfer reactions involving 10Be and 24Mg nuclear cores. Important effects of the core excitation are found, often improving the description of the experimental data. In the neutron transfer reactions the core excitation effect is by far not just a simple reduction of the cross section by the respective spectroscopic factor. This indicates that widely used extraction of the spectroscopic factors from the ratio of the experimental and theoretical transfer cross sections is unreliable approach.