Quasiparticle and γ -band structures in Dy 156

Excited band structures recently observed in Dy156 are investigated using the microscopic triaxial projected shell model (TPSM) approach and the quasiparticle random phase approximation (QRPA) based on the rotating mean field. It is demonstrated that new observed excited bands, tracking the ground-state band, are the γ bands based on the excited two-quasineutron configurations as conjectured in the experimental work.