GENERALIZED HARTREE-FOCK-BOGOLIUBOV APPROACH FOR THE DESCRIPTION OF BAND STRUCTURES IN NUCLEI .1. FORMULATION OF THE THEORY AND ITS EXACT SOLUTION IN THE FRAMEWORK OF THE SU(3) MODEL

The SU(3) model is studied in the framework of the generalized Hartree-Fock-Bogoliubov approach, proposed in the papers of Kerman and Klein, and Beliaev and Zelevinski. In this model the mentioned approach is equivalent to the exact solution of the problem. The generalized density matrix R defined in the product space of single-particle and nuclear states is calculated analytically. Its eigenvalues, the occupation numbers in the average field, differ essentially from one. Thus the normalization condition R2 = R used in the HFB theory is not valid in the generalized approach. © 1979.