An Extension of the Rotating Shell Model and Its Application to 164Er

Abstract
We develop an RPA approach based on rotating potentials as an extension of the rotating shell model of nuclear high-spin states. The RPA formalism is applied to the positive-parity yrast spectrum of 164Er. Properties at high spin of the pairing potentials and of the γ-vibrational bands are analyzed as functions of the rotational frequency. The result of calculation indicates an onset in the s-band of instability toward triaxial deformation.