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arXiv · 1209.0150

Tensor-optimized shell model for the Li isotopes with a bare nucleon-nucleon interaction

Takayuki Myo·Atsushi Umeya·Hiroshi Toki·Kiyomi Ikeda
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Abstract

We study the Li isotopes systematically in terms of the tensor-optimized shell model (TOSM) by using a bare nucleon-nucleon interaction as the AV8' interaction. The short-range correlation is treated in the unitary correlation operator method (UCOM). Using the TOSM+UCOM approach, we investigate the role of the tensor force on each spectrum of the Li isotopes. It is found that the tensor force produces quite a characteristic effect on various states in each spectrum and those spectra are affected considerably by the tensor force. The energy difference between the spin-orbit partner, the p1/2 and p3/2 orbits of the last neutron, in 5Li is caused by opposite roles of the tensor correlation. In 6Li, the spin-triplet state in the LS coupling configuration is favored energetically by the tensor force in comparison with jj coupling shell model states. In 7,8,9Li, the low-lying states containing extra neutrons in the p3/2 orbit are favored energetically due to the large tensor contribution to allow the excitation from the 0s orbit to the p1/2 orbit by the tensor force. Those three nuclei show the jj coupling character in their ground states which is different from 6Li.

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Takayuki Myo, Atsushi Umeya, Hiroshi Toki, Kiyomi Ikeda. 2012-09-02. Tensor-optimized shell model for the Li isotopes with a bare nucleon-nucleon interaction. https://doi.org/10.1103/physrevc.86.024318

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