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The fermion dynamical symmetry model for the even--even and even--odd nuclei in the Xe--Ba region

X. W. Pan·J. L. Ping·D. H. Feng·C. L. Wu·M. K. Guidry
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Abstract

The even--even and even--odd nuclei $^{126}$Xe-$^{132}$Xe and $^{131}$Ba-$^{137}$Ba are shown to have a well-realized $SO_8 \supset SO_6 \supset SO_3$ fermion dynamical symmetry. Their low-lying energy levels can be described by a unified analytical expression with two (three) adjustable parameters for even--odd (even--even) nuclei that is derived from the fermion dynamical symmetry model. Analytical expressions are given for wavefunctions and for $E2$ transition rates that agree well with data. The distinction between the FDSM and IBM $SO_6$ limits is discussed. The experimentally observed suppression of the the energy levels with increasing $SO_5$ quantum number $τ$ can be explained as a perturbation of the pairing interaction on the $SO_6$ symmetry, which leads to an $SO_5$ Pairing effect for $SO_6$ nuclei.

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X. W. Pan, J. L. Ping, D. H. Feng, C. L. Wu, M. K. Guidry. 1995-10-08. The fermion dynamical symmetry model for the even--even and even--odd nuclei in the Xe--Ba region. https://doi.org/10.1103/physrevc.53.715

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