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Microscopic Restoration of Proton-Neutron Mixed Symmetry in Weakly Collective Nuclei

J. D. Holt·N. Pietralla·J. W. Holt·T. T. S. Kuo·G. Rainovski
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Abstract

Starting from the microscopic low-momentum nucleon-nucleon interaction V{low k}, we present the first systematic shell model study of magnetic moments and magnetic dipole transition strengths of the basic low-energy one-quadrupole phonon excitations in nearly-spherical nuclei. Studying in particular the even-even N=52 isotones from 92Zr to 100Cd, we find the predicted evolution of the predominantly proton-neutron non-symmetric state reveals a restoration of collective proton-neutron mixed-symmetry structure near mid-shell. This provides the first explanation for the existence of pronounced collective mixed-symmetry structures in weakly-collective nuclei.

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J. D. Holt, N. Pietralla, J. W. Holt, T. T. S. Kuo, G. Rainovski. 2006-12-14. Microscopic Restoration of Proton-Neutron Mixed Symmetry in Weakly Collective Nuclei. https://doi.org/10.1103/physrevc.76.034325

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