Single particle degrees of freedom in the interacting boson model

Abstract

An overview is given of different aspects of the Interacting Boson Fermion Model, the extension of the interacting Boson Model to odd mass nuclei. The microscopic model for the coupling of single-particle degrees of freedom to the system of bosons is outlined and the interaction between the bosons and the single-particle is derived. The predictions of the model are compared to those of the standard geometrical models. As realistic examples calculations of the low-lying positive and negative parity states in the odd-mass Europium isotopes and of the spreading width of deeply-bound hole states in the odd-mass Palladium isotopes are presented. The concept of dynamical super-symmetries is outlined. Also the phenomenology and microscopy of the coupling of two-quasi-particles to the bosons is discussed.