Strong coupled and doubly decoupled bands in the SU BF (3) ⊗ U F (2j + 1) limit of interacting boson — fermion — fermion model

Abstract

The quantum numbers labelling the basis states and the corresponding strong coupled wavefunctions in the SU BF (3) ⊗ U F (2j + 1) limit of interacting boson — fermion — fermion model are given. This dynamical symmetry limit is appropriate for heavy deformed odd — odd nuclei for configurations with one of the odd particle (proton or neutron) occupying all the natural parity orbits in the corresponding valence shell and the other particle occupying a single j — orbit. A boson — fermion — fermion interaction that can change the positions of the strong coupled bands without admixing and generate degenerate quadruplet of bands is constructed. A simple spin — spin and spin — orbital interaction that splits and changes the positions of the members of the quadruplet of bands is given. Adding a coriolis term to the hamiltonian generates doubly decoupled bands such as those seen in 176Re nucleus.