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Anomalous rotational-alignment in N=Z nuclei and residual neutron-proton interaction

Yang Sun·Javid A. Sheikh
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Abstract

Recent experiments have demonstrated that the rotational-alignment for the $N=Z$ nuclei in the mass-80 region is considerably delayed as compared to the neighboring $N \ne Z$ nuclei. We investigate whether this observation can be understood by a known component of nuclear residual interactions. It is shown that the quadrupole-pairing interaction, which explains many of the delays known in rare-earth nuclei, does not produce the substantial delay observed for these $N=Z$ nuclei. However, the residual neutron-proton interaction which is conjectured to be relevant for $N=Z$ nuclei is shown to be quite important in explaining the new experimental data.

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Yang Sun, Javid A. Sheikh. 2001-07-05. Anomalous rotational-alignment in N=Z nuclei and residual neutron-proton interaction. https://doi.org/10.1103/physrevc.64.031302

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