The anomalous signature-dependence of proton ${\mathit{h}}_{11/2}$ rotational bands in ${}_{}{}^{155,157}{}_{}{}^{}\mathrm{Ho}$, ${}_{}{}^{159}{}_{}{}^{}\mathrm{Tm}$, ${}_{}{}^{161,163,165}{}_{}{}^{}\mathrm{Lu}$ after the first band crossing is described in the framework of a model of particles plus symmetric rotor. We take into account rotor’s degree of freedom that it undergoes γ vibration about an axially symmetric equilibrium deformation. By using a set of moments of inertia such that the largest one is around the shortest axis, the essential features of all the energy spectra are reproduced. We have calculated magnetic dipole and electric quadrupole transition strengths with the wave functions obtained, and have found that virtually every characteristic feature of the available experimental data is well reproduced.

• Received 1 March 1990

DOI:https://doi.org/10.1103/PhysRevC.42.149