INTERACTING VECTOR BOSON MODEL AND OTHER VERSIONS OF INTERACTING BOSON APPROXIMATIONS

The general features of the mapping of boson pairs on new bosons are investigated. The results obtained for exact boson mapping of the sp(2d, R) algebra on the u(d)-boson algebra are then applied to the special case of algebra sp(12, R) (d = 6) which is the dynamical symmetry algebra of the interaction vector boson model (IVBM). The Dyson mapping of the IVBM on a version of the standard IBM with dynamical symmetry U(21) is obtained. This version of IBM contains the S(T = 1), D(T = 1) and P(T = 0) bosons, where T is the isospin of the bosons. The problem of elimination of spurious states and Hermitization of this boson representation is discussed. The image of the IVBM Hamiltonian in the space of the S, D, P-bosons is found.