#### Bulg. J. Phys. vol.42 no.4 (2015), pp. 503-512

#### Interplay of γ-Rigid and γ-Stable Collective Motion in Neutron Rich Rare Earth Nuclei

R. Budaca

^{}, A.I. Budaca^{}*National Institute of Physics and Nuclear Engineering, 077125, Romania*Abstract.A simple exactly separable version of the Bohr Hamiltonian which combines theγ-stable andγ-rigid collective motion is used to describe few neutron rich rare earth nuclei. The coupling between the two types of collective motion is managed through a rigidity parameter. Considering a potential of the formu(β)+v(γ)/βadapted to the current problem and restricting the^{2}γ-stable part of the Hamiltonian to stiff oscillations around theγvalue of the rigid motion one obtains an exact separation of variables. Moreover, the separated potential forβ>/i> variable is chosen such that in the lower limit of the rigidity parameter, the model recovers exactly the ES-X(5)or ES-D solutions, while in the upper limit it tends to the prolate $\gamma$-rigid solutionsX(3)orX(3)-D. The experimental realization of the model is found in few transitional rare earth nuclei aroundN=96where a singular behaviour is observed.

#### Full-text: PDF

*go back*