The interacting boson model with SU(3) charge symmetry and its applicationto even-even N approximate to Z nuclei

The isospin-invariant interacting boson model IBM-3 is analyzed in situatio ns where SUT(3) charge symmetry (or, equivalently, U-L(6) sd symmetry) is c onserved. Analytic expressions for energies, electromagnetic transitions, t wo-nucleon transfer probabilities, and boson-number expectation values are obtained for the three possible dynamical symmetry limits, U(5), SU(3), and O(6). Results found in IBM-3 are related to corresponding ones in IBM-1 an d IBM-2. Numerical calculations are presented f(7/2)-shell nuclei and some features that distinguish IBM-3 from its predecessors IBM-1 and IBM-2 are p ointed out. (C) 1999 Academic Press.