Spin-dependent T softness or triaxiality in even-even ^132-138 Nd nuclei

The properties of γ instability in rapidly rotating even-even132-138 Nd isotopes have been investigated using the pairing-deformation self-consistent total-Routhian-surface calculations in a deformation space of(β2, γ,β4). It is found that even-even134-138 Nd nuclei exhibit triaxiality in both ground and excited states, even up to high-spin states. The lightest isotope possesses a well-deformed prolate shape without a γ deformation component.The current numerical results are compared with previous calculations and available observables such as quadrupole deformation β2 and the feature of γ-band levels, showing basically a general agreement with the observed trend ofγ correlations(e.g. the pattern of the odd-even energy staggering of the γ band). The existing differences between theory and experiment are analyzed and discussed briefly.