Nilsson and Interacting-Boson-Model Pictures of Deformed Nuclei

Abstract

Variational solutions of the pairing-plus-quadrupole Hamiltonian are obtained for a system of protons and neutrons moving in a set of degenerate single-particle orbitals. The role played by pairs of particles coupled to angular momentum $\lambda$ different from 0 and 2 has been studied. It is found that pairs of particles coupled to angular momentum $\lambda =4\mathrm{}$ are essential to obtain the properties of the ground state of deformed nuclei. Even pairs of particles coupled to angular momentum $\lambda =6\mathrm{}$ can play an important role in many cases.