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arXiv · 1804.08496

Particle number conserving BCS approach in the relativistic mean field model and its application to $^{32-74}$Ca

Rong An·Lisheng Geng·Shisheng Zhang·Lang Liu
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Abstract

A particle number conserving BCS approach (FBCS) is formulated in the relativistic mean field (RMF) model. It is shown that the so-obtained RMF+FBCS model can describe the weak pairing limit. We calculate the ground-state properties of the calcium isotopes $^{32-74}$Ca and compare the results with those obtained from the usual RMF+BCS model. Although the results are quite similar to each other, we observe an interesting phenomenon, i.e., for $^{54}$Ca, the FBCS approach can enhance the occupation probability of the $2p_{1/2}$ single particle level and slightly increases its radius, compared with the RMF+BCS model. This leads to an unusual scenario that although $^{54}$Ca is more bound with a spherical configuration but the corresponding size is not the most compact one. We anticipate that such a phenomenon might happen for other neutron rich nuclei and should be checked by further more systematic studies.

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Rong An, Lisheng Geng, Shisheng Zhang, Lang Liu. 2018-04-23. Particle number conserving BCS approach in the relativistic mean field model and its application to $^{32-74}$Ca. https://doi.org/10.1088/1674-1137%2F42%2F11%2F114101

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