Nuclear spin polarization following intermediate-energy heavy-ion reactions

TL;DR

This paper investigates how intermediate-energy heavy-ion collisions induce spin polarization in projectile-like fragments, using models that incorporate angular momentum conservation, realistic distributions, and gamma-ray effects for improved accuracy.

Contribution

It introduces refined models accounting for gamma-ray de-orientation and acceptance corrections, enhancing quantitative predictions of spin polarization in heavy-ion reactions.

Findings

Qualitative agreement with experimental data achieved

Inclusion of gamma-ray effects improves model accuracy

Corrections apply to both nucleon removal and pickup processes

Abstract

Intermediate-energy heavy-ion collisions can produce a spin polarization of the projectile-like species. Spin polarization has been observed for both nucleon removal and nucleon pickup processes. Qualitative agreement with measured spin polarization as a function of the momentum of the projectile-like fragment is found in a kinematical model that considers conservation of linear and angular momentum and assumes peripheral interactions between the fast projectile and target. Better quantitative agreement was reached by including more realistic angular distributions, de-orientation caused by gamma-ray emission, and by correcting for the out-of-plane acceptance. The newly introduced corrections were found to apply to both nucleon removal and nucleon pickup processes.