Strange baryons, nuclear dripline and shrinkage : A Relativistic Mean Field study

TL;DR

This study uses a relativistic mean field model to explore how hyperons affect the stability and size of nuclei near the driplines, revealing hyperons extend nuclear boundaries and cause shrinkage.

Contribution

It introduces an extended FSU Gold Lagrangian density to analyze hypernuclei, demonstrating hyperons' role in extending driplines and reducing nuclear radii.

Findings

Hyperons enable nuclei to exist beyond normal driplines.

Hypernuclei near driplines exhibit reduced radii.

Xi- hyperons cause larger radius reductions than Lambda hyperons.

Abstract

Neutron and proton driplines of single-$\Lambda$ and double-$\Lambda$ hypernuclei, $\Xi^{-}$ hypernuclei as well as normal nuclei are studied within a relativistic mean field approach using an extended form of the FSU Gold Lagrangian density. Hyperons are found to produce bound nuclei beyond the normal nuclear driplines. Radii are found to decrease in hypernuclei near the driplines, in line with observations in light $\Lambda$ hypernuclei near the stability valley, The inclusion of a $\Xi^{-}$ introduces a much larger change in radii than one or more $\Lambda$'s.