Nonrotational states in isotonic chains of heavy nuclei

The ground-state deformations of heavy nuclei are explored with the microscopic-macroscopic approach using the single-particle Woods-Saxon potential of the quasiparticle-phonon model. The calculations of the energies of low-lying nonrotational states take into account the residual pairing and phonon-quasiparticle interactions. The spectra of these states are presented for the N=147-161 isotones. The sensitivity of the calculated results to the parameters of the model is studied. A rather good description of the available experimental data is demonstrated.