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

Abstract

It is proposed that the odd-even staggering (OES) in the $\gamma$- 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 $\gamma$- bands ($L\ge 10$). It is shown that the OES can be interpreted reasonably as the result of the interaction of the $\gamma$ 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--$\gamma$ band-mixing interaction, showing that strong OES effect occurs in regions with strong ground--$\gamma$ band-mixing interaction. The approach used allows a detailed comparison of the OES in $\gamma$ bands with the other kinds of staggering effects in nuclei and diatomic molecules.

25 pages, 11 postscript figures

References in corpus (4)

• Broken SU(3) symmetry in deformed even-even nuclei
• Ground-$\gamma$ band coupling in heavy deformed nuclei and SU(3) contraction limit
• $\Delta I=4$ and $\Delta I=8$ bifurcations in rotational bands of diatomic molecules
• Quadrupole and Hexadecapole Correlations in Rotating Nuclei Studied within the Single-j Shell Model

Cited by in corpus (6)

• The proxy-SU(3) symmetry in atomic nuclei
• Partial dynamical symmetry as a selection criterion for many-body interactions
• Staggering behavior of 0^+ state energies in the Sp(4) pairing model
• Ground-gamma band mixing and evolution of collectivity in even-even neutron-rich nuclei with 40<Z<50
• Partial dynamical symmetry and odd-even staggering in deformed nuclei
• Rotations of nuclei with reflection asymmetry correlations