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arXiv · 1712.09954

Evolution of single-particle structure of silicon isotopes

O. Bespalova·N. Fedorov·A. Klimochkina·M. Markova·T. Spasskaya·T. Tretyakova
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Abstract

New data on proton and neutron single-particle energies $E_{nlj}$ of Si isotopes with neutron number $N$ from 12 to 28 as well as occupation probabilities $N_{nlj}$ of single particle states of stable isotopes $^{28,30}$Si near the Fermi energy were obtained by the joint evaluation of the stripping and pick-up reaction data and excited state decay schemes of neighboring nuclei. The evaluated data indicate following features of single-particle structure evolution: persistence of $Z = 14$ subshell closure with $N$ increase, the new magicity of the number $N = 16$, and the conservation of the magic properties of the number $N = 20$ in Si isotopic chain. The features were described by the dispersive optical model. The calculation also predicts the weakening of $N = 28$ shell closure and demonstrates evolution of bubble-like structure of the proton density distributions in neutron-rich Si isotopes.

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O. Bespalova, N. Fedorov, A. Klimochkina, M. Markova, T. Spasskaya, T. Tretyakova. 2017-12-28. Evolution of single-particle structure of silicon isotopes. https://doi.org/10.1140/epja%2Fi2018-12449-x

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