Description of odd- A nuclei in the Pt region in the interacting boson-fermion model

Abstract

Properties of unique parity states in odd-proton ( 77Ir, 79Au) and odd-neutron nuclei ( 78Pt) are investigated in the framework of the interacting boson-fermion approximation model. The core (boson)-particle (fermion) interaction is represented by a quadrupole-quadrupole interaction and an exchange term, which takes into account the effects of the Pauli exclusion principle. The even-even core nucleus is described in terms of the IBA-1 hamiltonian. The change in the properties of the corresponding odd- A nuclei can be interpreted in terms of a transition of the core hamiltonian between the O(6) and SU(3) limiting cases.