MICROSCOPIC DESCRIPTION OF E2 AND E3 GIANT-RESONANCES IN DEFORMED ANDSUPERDEFORMED NUCLEI

The vibrating potential model, which represents a self-consistent vers ion of the random-phase approximation (RPA) with a separable residual interaction, is generalized to the description of E lambda collective excitations in nuclei with any even-multipole static deformation. The model is used to study the isoscalar E2 and E3 giant resonances in def ormed and superdeformed Sm-154 and Dy-152. The importance of the nucle ar self-consistency is shown. The model provides a satisfactory descri ption of the isoscalar E2 and E3 giant resonances in deformed Sm-154, predicting a considerable washing out of these resonances, especially the octupole one, in superdeformed Dy-152. Th, latter result means tha t the experimental observation of the isoscalar giant resonance in sup erdeformed nuclei can encounter serious troubles.