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Structure of isomeric states in 66As and 67As

M. Hasegawa·Y. Sun·K. Kaneko·T. Mizusaki
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Abstract

Strong residual correlations between neutrons and protons in N ~ Z systems can lead to unusual structure. Using the spherical shell model, we show that a low-excitation shape isomer can occur in the odd-odd N=Z nucleus 66As. This extends the picture of shape coexistence beyond even-even nuclei. Furthermore, it is demonstrated that in 66As and in the N=Z+1 nucleus 67As, a new type of isomer, which we term j-isomer, can be formed. The underlying mechanism for the isomerism formation is structure change in the isomeric states, which involves either an alignment of a neutron-proton pair from the high-j intruder orbitals, or a simultaneous occupation of these neutron and proton high-j orbitals.

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M. Hasegawa, Y. Sun, K. Kaneko, T. Mizusaki. 2005-05-09. Structure of isomeric states in 66As and 67As. https://doi.org/10.1016/j.physletb.2005.05.027

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