We refine the theoretical treatment of two-neutron transfer between deformed nuclei of the rare-earth region and a heavy spherical nucleus in the Pb region. The refinement from our previous work on effects of the Berry phase interference around the backbending region is that we now include the two lowest rotational bands of both the A and A+2 nucleus rather than the lowest. The inclusion of two bands, ground and aligned, was earlier done by Dasso and Winther, who found diabolic interference effects to be small. We make numerical calculations on somewhat more favorable cases for experimental study, and we include nuclear optical potential effects and finite ${\mathit{Q}}_{\mathit{r}\mathit{x}}$ values.

• Received 18 February 1992

DOI:https://doi.org/10.1103/PhysRevC.47.2836