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arXiv · 1202.3916

Coherence features of the spin-aligned neutron-proton pair coupling scheme

C. Qi·J. Blomqvist·T. Bäck·B. Cederwall·A. Johnson·R. J. Liotta·R. Wyss
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Abstract

The seniority scheme has been shown to be extremely useful for the classification of nuclear states in semi-magic nuclei. The neutron-proton ($np$) correlation breaks the seniority symmetry in a major way. As a result, the corresponding wave function is a mixture of many components with different seniority quantum numbers. In this contribution we show that the $np$ interaction may favor a new kind of coupling in $N=Z$ nuclei, i.e., the so-called isoscalar spin-aligned $np$ pair mode. Shell model calculations reveal that the ground and low-lying yrast states of the $N = Z$ nuclei $^{92}$Pd and $^{96}$Cd may mainly be built upon such spin-aligned $np$ pairs each carrying the maximum angular momentum $J = 9$ allowed by the shell $0g_{9/2}$ which is dominant in this nuclear region.

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C. Qi, J. Blomqvist, T. Bäck, B. Cederwall, A. Johnson, R. J. Liotta, R. Wyss. 2012-02-17. Coherence features of the spin-aligned neutron-proton pair coupling scheme. https://doi.org/10.1088/0031-8949%2F2012%2Ft150%2F014031

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