M1 strengths in deformed nuclei
Abstract
The Elliott SU(3) model, extended via pseudo-spin for heavy nuclei, is used to study low-lying magnetic dipole excitations in deformed nuclei. Proton and neutron degrees of freedom are handled explicitly and the system Hamiltonian includes single-particle energies as well as quadrupole-quadrupole and pairing two-body interactions. The calculated excitation spectra and M1 strength distribution of the strongly deformed even-even 156-160Gd isotopes are shown to be in good agreement with experimental results. Results for the γ-unstable (soft rotor) 196Pt nucleus and the even-odd 163Dy system are also reported and found to compare favourably with the available experimental data, demonstrating the ability of the model to describe very different types of systems.