The quadrupole moments $Q_0$ of five superdeformed bands in ${}^{131,132}\mathrm{Ce}$ have been established using the Doppler-shift attenuation method; for the first time, we can compare relative deformations of yrast and excited bands in different nuclei to an accuracy of $\simeq (5–7)\%$. Four of the five bands have very similar deformations, while the excited band in ${}^{131}\mathrm{Ce}$ has a somewhat larger quadrupole moment. Important new information is presented on the shape-driving force of the $\nu i_{13/2}$ orbital, the stability of the second minimum with respect to particle excitations, the relative deformations of identical bands, the nature of the sidefeeding, and the time scale of the decay process.

• Received 11 December 1995

DOI:https://doi.org/10.1103/PhysRevLett.76.3510