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Ground-gamma band mixing and odd-even staggering in heavy deformed nuclei

Nikolay Minkov·S. B. Drenska·P. P. Raychev·R. P. Roussev·Dennis Bonatsos
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Abstract

It is proposed that the odd-even staggering (OES) in the $γ$- bands of heavy deformed nuclei can be reasonably characterized by a discrete approximation of the fourth derivative of the odd-even energy difference as a function of angular momentum $L$. This quantity exhibits a well developed staggering pattern (zigzagging behavior with alternating signs) in rare earth nuclei and actinides with long $γ$- bands ($L\geq 10$). It is shown that the OES can be interpreted reasonably as the result of the interaction of the $γ$ band with the ground band in the framework of a Vector Boson Model with SU(3) dynamical symmetry. The model energy expression reproduces successfully the staggering pattern in all considered nuclei up to $L=12-13$. The general behavior of the OES effect in rotational regions is studied in terms of the ground--$γ$ band-mixing interaction, showing that strong OES effect occurs in regions with strong ground--$γ$ band-mixing interaction. The approach used allows a detailed comparison of the OES in $γ$ bands with the other kinds of staggering effects in nuclei and diatomic molecules.

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Nikolay Minkov, S. B. Drenska, P. P. Raychev, R. P. Roussev, Dennis Bonatsos. 2000-10-22. Ground-gamma band mixing and odd-even staggering in heavy deformed nuclei. https://doi.org/10.1103/physrevc.61.064301

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