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Violation and persistence of the K-quantum number in warm rotating nuclei

M. Matsuo·T. Dossing·A. Bracco·G. B. Hagemann·B. Herskind·S. Leoni·E. Vigezzi
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Abstract

The validity of the K-quantum number in rapidly rotating warm nuclei is investigated as a function of thermal excitation energy U and angular momentum I, for the rare-earth nucleus 163Er. The quantal eigenstates are described with a shell model which combines a cranked Nilsson mean-field and a residual two-body interaction, together with a term which takes into account the angular momentum carried by the K-quantum number in an approximate way. K-mixing is produced by the interplay of the Coriolis interaction and the residual interaction; it is weak in the region of the discrete rotational bands (U \lesim 1MeV), but it gradually increases until the limit of complete violation of the K-quantum number is approached around U \sim 2 - 2.5 MeV. The calculated matrix elements between bands having different K-quantum numbers decrease exponentially as a function of $ΔK$, in qualitative agreement with recent data.

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M. Matsuo, T. Dossing, A. Bracco, G. B. Hagemann, B. Herskind, S. Leoni, E. Vigezzi. 2004-03-10. Violation and persistence of the K-quantum number in warm rotating nuclei. https://doi.org/10.1016/j.nuclphysa.2004.03.004

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