New Studies on the Aspects of Nuclear Shapes

Using the pairing-deformation-frequency self-consistent total-Routhian-surface and configuration-constrained potential-energy-surface calculations,1 we have studied nuclear deformation and its effect on the structure of nuclei. It was found that the high-order multipolarity-six (beta(6)) deformation plays a significant role in superheavy nuclei. Possible non-collective high-spin isomeric states which locate in the second well of actinide nuclei have been investigated with the predictions of excitation energies and configurations. High-spin isomers can extend shape coexistence in A similar to 190 neutron-deficient nuclei. Triaxiality with gamma similar to 30 degrees is found in the ground and excited rotational states of the A similar to 70 germanium isotopes. Octupole correlations have also been discussed in different mass regions. In recent experiments, the textbook nucleus Er-158 has been reached at ultrahigh spins around 65 (h) over bar. We have studied Er-158 ultrahigh-spin states by means of the self-consistent tilted-axis-cranking method based on the Nilsson shell correction and the Skyrme-Hartree-Fock model. The calculation with a gamma approximate to 12 degrees triaxial-strongly-deformed (TSD) excited configuration can well reproduce the observed large transitional quadrupole moment.. It is demonstrated that the TSD minimum at negative gamma deformation which appears in the principal-axis-cranking approach is a saddle point if allowing the rotational axis to change direction. DOI:10.5506/APhysPolB.44.271