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arXiv · 1804.06558

Disappearance of nuclear deformation in hypernuclei: a perspective from a beyond-mean-field study

H. Mei·K. Hagino·J. M. Yao·T. Motoba
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Abstract

The previous mean-field calculation [Myaing Thi Win and K. Hagino, Phys. Rev. C{\bf 78}, 054311 (2008)] has shown that the oblate deformation in $^{28,30,32}$Si disappears when a $\Lambda$ particle is added to these nuclei. We here investigate this phenomenon by taking into account the effects beyond the mean-field approximation. To this end, we employ the microscopic particle-rotor model based on the covariant density functional theory. We show that the deformation of $^{30}$Si does not completely disappear, even though it is somewhat reduced, after a $\Lambda$ particle is added if the beyond-mean-field effect is taken into account. We also discuss the impurity effect of $\Lambda$ particle on the electric quadrupole transition, and show that an addition of a $\Lambda$ particle leads to a reduction in the $B(E2)$ value, as a consequence of the reduction in the deformation parameter.

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H. Mei, K. Hagino, J. M. Yao, T. Motoba. 2018-04-18. Disappearance of nuclear deformation in hypernuclei: a perspective from a beyond-mean-field study. https://doi.org/10.1103/physrevc.97.064318

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