Asymmetrical rotator approximation for even-even nuclei with quadrupole and octupole deformations

Energy levels of the excited states with alternating parity of the deformable nonaxial even-even nuclei with quadrupole and octupole deformations are investigated on the framework collective model. With using four fitting parameters for described energy levels of the excited states of the even-even nuclei 154,160,162Dy, 164Er and 220Ra are obtained results which are in good agreement with experimental data at low energies of the excited states. (authors)