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Regularity and Chaos in low-lying 2+ states of even-even nuclei

A. Y. Abul--Magd·H. L. Harney·M. H. Simbel·H. A. Weidenmueller
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Abstract

Using all the available empirical information, we analyse the spacing distributions of low-lying 2+ levels in even-even nuclei by comparing them with a theoretical distribution characterized by a single parameter (the chaoticity parameter f). We use the method of Bayesian inference. We show that the necessary unfolding procedure generally leads to an overestimate of f. We find that f varies strongly with the ratio of the excitation energies of the first 4+ and 2+ levels and assumes particularly small values in nuclei that have one of the dynamical symmetries of the Interacting Boson Model.

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A. Y. Abul--Magd, H. L. Harney, M. H. Simbel, H. A. Weidenmueller. 2003-04-09. Regularity and Chaos in low-lying 2+ states of even-even nuclei. https://doi.org/10.1142/9789812702760_0049

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