Clusterization and deformation of multi-$\Lambda$ hypernuclei within relativistic mean-field model

Abstract

Deformed multi-$\Lambda$ hypernuclei are studied within a relativistic mean-field model. In this paper, we take some $N=Z$ "hyper isotope" chains, i.e., $^{8+n}_{\ \ n\Lambda}{\rm Be}$, $^{20+n}_{\ \ \ n\Lambda}{\rm Ne}$, and $^{28+n}_{\ \ \ n\Lambda}{\rm Si}$ systems where $n = 2$, $4$ for Be, and $n = 2$, $8$ for Ne and Si. A sign of two-$^6_{2\Lambda}$He cluster structure is observed in the two-body correlation in $^{12}_{4\Lambda}$Be. In the Ne hyper isotopes, the deformation is slightly reduced by addition of $\Lambda$ hyperons whereas it is significantly reduced or even disappears in the Si hyper isotopes.