Deformation of Lambda hypernuclei

TL;DR

This paper investigates how the addition of a Lambda hyperon affects the shape deformation of hypernuclei using the relativistic mean field approach, revealing shape changes in specific cases and consistency with prior models.

Contribution

It provides new insights into the deformation properties of Lambda hypernuclei using the relativistic mean field method, comparing results with previous non-relativistic studies.

Findings

$^{29}_{\Lambda}$Si and $^{13}_{\Lambda}$C are spherical due to the Lambda particle.

Most hypernuclei have similar deformation to their core nuclei.

Results are sensitive to pairing interactions and RMF parameter sets.

Abstract

We study the deformation property of $\Lambda$ hypernuclei using the relativistic mean field (RMF) method. We find that $^{29}_{\Lambda}$Si and $^{13}_{\Lambda}$C hypernuclei have spherical shape as a consequence of the additional $\Lambda$ particle, whereas the corresponding core nuclei, $^{28}$Si and $^{12}$C, are oblately deformed. Most of other hypernuclei have a similar deformation parameter to the core nucleus, in accordance with the previous study with the non-relativistic Skyrme-Hartree-Fock method. We discuss the sensitivity of our results to the choice of pairing interaction and to the parameter set of the RMF Lagrangian.