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Unique features of structure in an odd-proton $N \approx Z$ nucleus $^{69}$As

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

We apply a large-scale shell model to the study of proton-rich odd-mass nuclei with $N \approx Z$. Calculations predict unexpected structure in the $^{69}$As nucleus for which a detailed experiment was recently performed. In this odd-proton nucleus, one neutron competes with one proton for occupying the high-$j$ intruder orbit $g_{9/2}$ in the $9/2_1^+$ state and almost solely occupies the $g_{9/2}$ orbit in other low-lying positive-parity states. The T=0, J=9 one-proton-one-neutron alignment takes place in the negative-parity states with medium-high spins. A unique coexistence of two lowest bands with positive and negative signs of spectroscopic quadrupole moments is predicted.

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M. Hasegawa, K. Kaneko, T. Mizusaki. 2005-11-07. Unique features of structure in an odd-proton $N \approx Z$ nucleus $^{69}$As. https://doi.org/10.1103/physrevc.72.064320

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