PHENOMENOLOGY OF NUCLEI AT VERY HIGH ANGULAR MOMENTA USING PARAMETRIZED TWO-CENTER NUCLEAR SHAPES

Abstract

The nuclear shapes and variation of moment of inertia with angular momentum, as well as the limiting angular momentum carried by a nucleus at its fissioning stage, are derived from the observed data of the ground-state yrast band and quadrupole deformations of these states. The necking-in of the nuclear shapes are shown to start already at J*~14+−18+. The empirical variation of moment of inertia with angular momentum is found to include the back-bending and forward-bending effects and supports the nuclear softness model of the nucleus. The fission of nuclei is shown to occur at very high angular momenta, which is different for different nuclei. The role of deformation energy is analyzed and the possibility of predicting the quadrupole deformations, or B(E2) transitions, for very high spin states is discussed. The calculations are presented for 156Dy, 158Er, and 164Hf.