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arXiv · 1010.5561

Shape of Lambda hypernuclei in (beta,gamma) deformation plane

Myaing Thi Win·K. Hagino·T. Koike
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Abstract

We study the shape of $\Lambda$ hypernuclei in the full ($\beta,\gamma$) deformation plane, including both axially symmetric and triaxial quadrupole deformations. To this end, we use the constrained Skyrme Hartree-Fock+BCS method on the three-dimensional Cartesian mesh. The potential energy surface is analyzed for carbon hypernuclei as well as for sd-shell hypernuclei such as $^{27,29}_{\Lambda}$Si and $^{25,27}_{\Lambda}$Mg. We show that the potential energy surface in the ($\beta,\gamma$) plane is similar to each other between the hypernuclei and the corresponding core nuclei, although the addition of $\Lambda$ hyperon makes the energy surface somewhat softer along the $\gamma$ direction. Our calculation implies that the energy of the $\gamma$ vibration for $^{25,27}_{\Lambda}$Mg nuclei is lowered by about 0.15 MeV with respect to that of $^{24,26}$Mg nuclei.

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Myaing Thi Win, K. Hagino, T. Koike. 2010-10-27. Shape of Lambda hypernuclei in (beta,gamma) deformation plane. https://doi.org/10.1103/physrevc.83.014301

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