Effects of $\bm\la$ hyperons on the deformations of even-even nuclei

TL;DR

This study investigates how the addition of lambda hyperons affects the shape deformations of even-even hypernuclei from beryllium to calcium, revealing deformation reductions or enhancements depending on hyperon number.

Contribution

It introduces a detailed analysis of hyperon-induced deformation changes in hypernuclei using the deformed Skyrme-Hartree-Fock approach, highlighting the role of specific hyperon orbit fillings.

Findings

Deformations decrease with 2 or 8 hyperons.

Deformations increase with 4 or 6 hyperons.

Hyperon filling influences nuclear shape changes.

Abstract

The deformations of multi-$\la$ hypernuclei corresponding to even-even core nuclei ranging from $^8$Be to $^{40}$Ca with 2, 4, 6, and 8 hyperons are studied in the framework of the deformed Skyrme-Hartree-Fock approach. It is found that the deformations are reduced when adding 2 or 8 $\la$ hyperons, but enhanced when adding 4 or 6 $\la$ hyperons. These differences are attributed to the fact that $\la$ hyperons are filled gradually into the three deformed $p$ orbits, of which the [110]1/2$^-$ orbit is prolately deformed and the degenerate [101]1/2$^-$ and [101]3/2$^-$ orbits are oblately deformed.