Wobbling motion in atomic nuclei with positive-γ shapes

The three moments of inertia associated with the wobbling mode built on the superdeformed states in ¹⁶³Lu are investigated by means of the cranked shell model plus random phase approximation to the configuration with an aligned quasiparticle. The result indicates that it is crucial to take into account the direct contribution to the moments of inertia from the aligned quasiparticle so as to realize ℑ_x>ℑ_y in positive-γ shapes. Quenching of the pairing gap cooperates with the alignment effect. The peculiarity of the recently observed ¹⁶³Lu data is discussed by calculating not only the electromagnetic properties but also the excitation spectra.