The analytical solution of the confined β-soft (CBS) rotor model is systematically compared to the energies of the ground-state rotational bands of strongly deformed heavy even-even nuclei. The model reproduces with one structural parameter the yrast band energies for all sufficiently well known rare-earth nuclei and actinides with a structural signature of $R_{4/2}=E(4_1^{+})/E(2_1^{+})>3.30$ up to the ${12}^{+}$ state with an accuracy of the order of ${10}^{-3}$. This systematic study of the CBS model demonstrates the regularity of the ground-state bands without exception. Comparison to the Davydov Chaban model suggests that the agreement between data and collective models with soft potentials is insensitive to the details of the potential.

• Received 14 September 2004

DOI:https://doi.org/10.1103/PhysRevC.72.011303