Importance of resonance widths in low-energy scattering of weakly-bound light-mass nuclei

TL;DR

This paper introduces a new method for modeling low-energy nuclear scattering involving weakly-bound nuclei, accurately accounting for resonance widths to improve agreement with experimental data.

Contribution

A novel approach is developed to describe resonant nuclear scattering with particle unstable resonances, avoiding unphysical behaviors of previous models.

Findings

Cross sections are more physically accurate with the new method.

Resonance widths significantly affect scattering results.

Better match to observed resonance data.

Abstract

What effect do particle-emitting resonances have on the scattering cross section? What physical considerations are necessary when modelling these resonances? These questions are important when theoretically describing scattering experiments with radioactive ion beams which investigate the frontiers of the table of nuclides, far from stability. Herein, a novel method is developed that describes resonant nuclear scattering from which centroids and widths in the compound nucleus are obtained when one of the interacting bodies has particle unstable resonances. The method gives cross sections without unphysical behavior that is found if simple Lorentzian forms are used to describe resonant target states. The resultant cross sections differ significantly from those obtained when the states in the coupled channel calculations are taken to have zero width, and compound-system resonances are better matched to observed values.