Underlying physics of identical odd- and even-mass bands in normally deformed rare-earth nuclei

The microscopic mechanism of the identical odd- and even-mass number nuclea r bands in normally deformed rare-earth nuclei was investigated using the p article-number conserving (PNC) method for treating nuclear pairing correla tion. It was found that the odd particle of an odd-A identical band always occupied a cranked low j and high Ohm Nilsson orbital (e. g. proton [404]7/ 2, [402]5/2). On the contrary, if the odd particle occupies an intruder hig h j orbital (e. g. neutron [633]7/2, proton [514]9/2), the moment of inerti a of the odd-A band was much larger than that of neighboring even-even grou nd state band. The observed variation of moment of inertia (below bandcross ing) was reproduced quite well by the PNC calculation, in which no free par ameter was involved. The strengths of monopole and Y-20 quadrupole interact ions were determined by the experimental odd-even differences in binding en ergy and bandhead moment of inertia.