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Isovector Pairing in Odd-A Proton-Rich Nuclei

Jonathan Engel·Karlheinz Langanke·Petr Vogel
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Abstract

A simple model based on the group SO(5) suggests that both the like-particle and neutron-proton components of isovector pairing correlations in odd-A nuclei are Pauli blocked. The same effect emerges from Monte Carlo Shell-model calculations of proton-rich nuclei in the full fp shell. There are small differences between the two models in their representation of the effects of an odd nucleon on the competition between like-particle and neutron-proton pairing, but they can be understood and reduced by using a two-level version of the SO(5) model. On the other hand, in odd-odd nuclei with N not equal to Z SO(5) disagrees more severely with the shell model because it incorrectly predicts ground-state isospins. The shell model calculations for any fp-shell nuclei can be extended to finite temperature, where they show a decrease in blocking.

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Jonathan Engel, Karlheinz Langanke, Petr Vogel. 1998-03-05. Isovector Pairing in Odd-A Proton-Rich Nuclei. https://doi.org/10.1016/s0370-2693(98)00477-8

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