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Broken SU(3) symmetry in deformed even-even nuclei

N. Minkov·S. B. Drenska·P. P. Raychev·R. P. Roussev·D. Bonatsos
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Abstract

A collective vector-boson model with broken SU(3) symmetry, in which the ground state band and the lowest $γ$ band belong to the same irreducible representation but are non-degenerate, is applied to several deformed even-even nuclei. The model description of ground and $γ$ bands together with the corresponding B(E2) transition probabilities is investigated within a broad range of SU(3) irreducible representations $(λ,μ)$. The calculations show that the $(λ,μ)$ characteristics of rotational nuclei depend to a great extent on the magnitude of the SU(3) splitting between the ground and $γ$ bands. It is found that for weakly split spectra, the ground--$γ$ band coupling scheme is realized relevantly within narrow regions of ``favored'' $(λ,μ)$ multiplets, while in the cases of strong splitting a description in which the ground band is situated alone in an irreducible representation is favored. The obtained results are analyzed in terms of the bandmixing interactions. The possibility for a transition between the different collective SU(3) schemes is discussed.

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N. Minkov, S. B. Drenska, P. P. Raychev, R. P. Roussev, D. Bonatsos. 1997-02-28. Broken SU(3) symmetry in deformed even-even nuclei. https://doi.org/10.1103/physrevc.55.2345

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