Analysis of collective and effective moments of inertia for 164Dy and 156Dy

Abstract We calculate the yrast lines for 164 Dy and 156 Dy in the spin region from 0ℏ to 50ℏ by using a cranking HFB model. Band crossings and spin alignments are analysed from the HFB wave functions. An effective and a collective moment of inertia are extracted from the yrast line, as suggested by the alignment model. Our calculation being quite similar to this model leads to the result that the collective moment of inertia drops below the effective one for high spins.