Systematic analysis of $\Delta I = 4$ bifurcation in $A \approx 150$ superdeformed nuclei : Active orbitals
A simple criterion for the \Delta I = 4 bifurcation is applied to thirty superdeformed bands in the A~150 mass region. The analysis allows to differentiate between active and inactive for staggering single-particle states. The consideration is based on additivity of nonaxial hexadecapole moment, which plays a key role in the phenomenon.