Phonon and multi-phonon excitations in rotational nuclei by exact diagonalization of the Bohr Hamiltonian

Exact numerical diagonalization of the Bohr Hamiltonian by SU(1,1)×SO(5)SU(1,1)×SO(5) methods is used to obtain detailed quantitative predictions for single-phonon and multi-phonon excitations in well-deformed rotor nuclei. Dynamical γ deformation is found to significantly influence the predictions through its coupling to the rotational motion. Basic signatures for the onset of rigid triaxial deformation are obtained.