Parity reversion in ^{12}_\Lambda Be

TL;DR

This study predicts a parity reversion in the hypernucleus $^{12}_\Lambda$Be caused by the impurity effect of a $\Lambda$ particle, highlighting the impact of $\Lambda$ binding energy differences on nuclear structure.

Contribution

It introduces an extended antisymmetrized molecular dynamics approach to hypernuclei, revealing a novel parity reversion phenomenon due to $\Lambda$ impurity effects.

Findings

Positive-parity ground state predicted for $^{12}_\Lambda$Be

Parity reversion caused by $\Lambda$ impurity effect

Difference in $\Lambda$ binding energy influences nuclear parity

Abstract

The spectrum of $^{12}_\Lambda$Be is studied by an extended version of antisymmetrized molecular dynamics for hypernuclei. The result predicts the positive-parity ground state of $^{12}_\Lambda$Be that is reverted to the normal one by the impurity effect of $\Lambda$ particle. The reversion of the parity is due to the difference of $\Lambda$ binding energy in the positive- and negative-parity states that originates in the difference of $\alpha$ clustering and deformation.