Supersymmetries with Neutrons and Protons

Abstract

In this chapter we present the logical combination of ideas introduced previously. In Chap. 4 fermion degrees of freedom were introduced in the interacting boson model (IBM), leading to a description of odd-mass nuclei in the context of the interacting boson–fermion model (IBFM) and, after due consideration of the appropriate superalgebras, to a simultaneous description of even–even and odd-mass nuclei. The purpose of Chap. 5, on the other hand, was the introduction of the F-spin degree of freedom in the IBM to distinguish between neutron and proton bosons, with several consequences such as a better microscopic foundation of the IBM, the existence of F-spin multiplets of nuclei, and the occurrence of states with a mixed-symmetry character in neutrons and protons.