Reaction cross sections of hypernuclei and the shrinkage effect

TL;DR

This study calculates reaction cross sections of lithium isotopes with and without a lambda particle, demonstrating a shrinkage effect due to the lambda particle using advanced Glauber theory beyond the optical limit.

Contribution

It introduces a few-body Glauber theory approach to quantify the shrinkage effect in hypernuclei, specifically for $^7_{\Lambda}{ m Li}$ compared to $^6$Li.

Findings

Reaction cross section for $^7_{\Lambda}{ m Li}$ is about 4% smaller than for $^6$Li.

The shrinkage effect of the lambda particle is quantitatively demonstrated.

The approach goes beyond the optical limit approximation in Glauber theory.

Abstract

We calculate the reaction cross sections for $^6{\rm Li}$ and $^7_{\Lambda}{\rm Li}$ on a $^{12}{\rm C}$ target at $100\,{\rm MeV/nucleon}$ using the Glauber theory. To this end, we assume a two-body cluster structure for $^6$Li and $^7_{\Lambda}{\rm Li}$, and employ the few-body treatment of the Glauber theory, that is beyond the well known optical limit approximation. We show that the reaction cross section for $^7_{\Lambda}{\rm Li}$ is smaller than that for $^6$Li by about 4\%, reflecting the shrinkage effect of the $\Lambda$ particle.