Systematics of band moment of inertia of yrast and excited SD bands of even–even nuclei in A~150 mass region

A four parameter formula has been applied to all the yrast and excited superdeformed (SD) bands of even–even nuclei in the A~150 mass region to obtain band moment of inertia J₀. In even–even nuclei, totally three yrast SD bands and 16 excited SD bands have been fitted. The measured Q_t values and hence the axes ratios have been used to calculate the rigid body J₀ values and compared with the fitted values of J₀. It is interesting to look at the yrast SD band ¹⁵²Dy(1), the doubly magic SD nucleus and the first one to be discovered that the J₀ values are quite larger than that extracted from Q_t measurement. We found that all the excited SD bands in even–even nuclei are signature partner SD bands because the J₀ value of each signature partner SD band is almost identical. Among all these excited SD bands, ¹⁵⁰Gd(4) is found to be super-rigid in nature having J₀ value larger than that observed from the measured Q_t value. (author)