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Signature inversion -- manifestation of drift of the rotational axis in triaxial nuclei

Zao-Chun Gao·Y. S. Chen·Yang Sun
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Abstract

A possible scheme of realizing shell model calculations for heavy nuclei is based on a deformed basis and the projection technique. Here we present a new development for odd-odd nuclei, in which one starts with triaxially-deformed multi-quasi-particle configurations, builds the shell-model space through exact three-dimensional angular-momentum-projection, and diagonalizes a two-body Hamiltonian in this space. The model enables us to study the old problem of signature inversion from a different view. With an excellent reproduction of the experimental data in the mass-130 region, the results tend to interpret the phenomenon as a manifestation of dynamical drift of the rotational axis with presence of axial asymmetry in these nuclei.

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Zao-Chun Gao, Y. S. Chen, Yang Sun. 2006-01-03. Signature inversion -- manifestation of drift of the rotational axis in triaxial nuclei. https://doi.org/10.1016/j.physletb.2006.01.033

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