SEMIMICROSCOPIC ALGEBRAIC CLUSTER MODEL OF LIGHT-NUCLEI .1. 2-CLUSTER-SYSTEMS WITH SPIN ISOSPIN-FREE INTERACTIONS

The relation of the phenomenological algebraic cluster model, i.e., of the vibron model and its extensions, to the microscopic description is discussed. Based on this connection a semimicroscopic approach is formulated, in which the internal cluster degrees of freedom are treated in terms of the SU(3) shell model, and the relative motion is described by the vibron model. For a two-cluster system this model has a group structure of U(C1)ST,(4) x U(C1)(3) x U(R)(4) x U(C2)(3) x U(C2)ST(4), and the phenomenological interactions are obtained in terms of the group generators. The model space is constructed to be free from the Pauli-forbidden states and spurious center of mass motion, similar to that of the SU(3) cluster model. Three examples, the C-12 + alpha, the C-12+ C-12 and the C-14 + alpha systems are presented to demonstrate various aspects of the semimicroscopic algebraic cluster model. (C) 1994 Academic Press, Inc.