Configuration-dependent effect of Δ I=4 bifurcation in A∼150 superdeformed nuclei: active and inactive orbitals

A simple criterion for the Δ I=4 bifurcation is applied to 22 superdeformed bands in the A∼150 mass region. An analysis confirms the configuration dependence effect and allows us to discriminate between single-particle states that are active and inactive for staggering. The consideration is based on additivity of the nonaxial quadrupole and hexadecapole moments. The analysis shows the correlation between the nonaxial hexadecapole moment of single-particle orbitals involved in the configurations of superdeformed bands and their staggering behaviour. (author)