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arXiv · 0903.3093

Deformation and weak decay of Lambda hypernuclei

K. Hagino·Myaing Thi Win·Y. Nakagawa
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Abstract

We use the self-consistent mean-field theory to discuss the ground state and decay properties of $\Lambda$ hypernuclei. We first discuss the deformation of $\Lambda$ hypernuclei using the relativistic mean-field (RMF) approach. We show that, although most of hypernuclei have a similar deformation parameter to the core nucleus, the shape of $^{28}$Si is drastically altered, from oblately deformed to spherical, if a $\Lambda$ particle is added to this nucleus. We then discuss the pionic weak decay of neutron-rich $\Lambda$ hypernuclei using the Skyrme Hartree-Fock + BCS method. We show that, for a given isotope chain, the decay rate increases as a function of mass number, due to the strong neutron-proton interaction.

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K. Hagino, Myaing Thi Win, Y. Nakagawa. 2009-03-18. Deformation and weak decay of Lambda hypernuclei. https://doi.org/10.1142/s0218301310017071

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