Microscopic mechanism of normally deformed identical bands at low spin in the rare-earth nuclei

The microscopic mechanism of identical normally deformed bands at low spin in the rare-earth nuclei is investigated using a particle-number conserving (PNC) treatment of the cranked shell model Hamiltonian. The observed identical seniority-zero, -one, and -two bands are reproduced quite well by the PNC calculation, in which no free parameter is involved. The influence of blocking effects on moments of inertia depends sensitively on the location and Coriolis response of the blocked levels. The crucial point is that the blocking effect must be taken into account strictly and consistently for the identical bands.