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arXiv · 1511.09306

Beyond-mean-field approach to low-lying spectra of $\Lambda$ hypernuclei

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

Taking the hypernucleus $^{13}_{~\Lambda}$C as an example, we illustrate the miscroscopic particle-rotor model for low-lying spectra of hypernuclei. This approach is based on the beyond-mean-field method, with the particle number and angular momentum projections. The quantum fluctuation of the mean-field is also taken into account for the core nucleus using the generator coordinate method. We show that the impurity effect of $\Lambda$ hyperon, such as a change in $B(E2)$, is well described with this model. Our calculation indicates that the most important impurity effect in $sd$-shell hypernuclei is a change in a deformation parameter rather than in a nuclear size.

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K. Hagino, H. Mei, J. M. Yao, T. Motoba. 2015-11-30. Beyond-mean-field approach to low-lying spectra of $\Lambda$ hypernuclei. https://arxiv.org/abs/1511.09306

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