ROTATIONAL STATES IN DEFORMED EVEN–EVEN NUCLEI

Abstract

The deviations from the simple I(I + 1) dependence of the energy levels in the ground-state rotational bands on the hydrodynamical model of Bohr and Mottelson have been investigated for both regions of stable deformation. An interpretation of high spin states is looked for in terms of a nonrigid rotator with vibrations (harmonic oscillator type) taken as perturbation. In the framework of this model, the energy expression is obtained as a power series in the product of the ratio B/A and the weight factor I(I + 1), where A is related to the moment of inertia and B is the rotation–vibration coupling constant. The calculations are shown to be in good agreement with the experimental data.