Quasirotational states in vibrational nuclei

Abstract In these lectures we present some simple characteristics excitational patterns in transitional nuclei approached from the viewpoint of strongly deformed and spherical nuclei. The sign and magnitude of the product Q ( j ) Q (2 1 ) are responsible for the tendency to increase or decrease the “deformation” of a coupled system, relative to Q (2 1 ), and to produce strongly coupled or decoupled excitational patterns. The vibrational picture is used for classification of states in a coupled system, in terms of multiplets, and the concept of intruder states is introduced toraccount for irregularities in the yrast band. Evidence is given for states arising from coupling clusters to collective states, especially those connected with internal excitations of a cluster.