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Based on our previous works about the configuration-constrained potential-energy-surface model investigating multi-quasiparticle high-K states, we have further developed the cranking configuration-constrained total Routhian surface method to calculate the collective rotations of the multiquasiparticle high-K states. The non-axial deformed Woods-Saxon potential has been adopted to obtain single-particle levels. The Woods-Saxon potential gives excellent single-particle level spacing, which is very important for the excitation energy calculations of high-K states. In order to improve pairing calculations, a particle-number-conserving pairing method has been incorporated into the TRS calculation. The calculated moments of inertia can well reproduce experimental values. The structures of the high-K states can be analyzed by the calculations. [ABSTRACT FROM AUTHOR]

Using the pairing-deformation-frequency self-consistent total-Routhian-surface and configuration-constrained potential-energy-surface calculations, we have studied nuclear deformation and its effect on the structure of nuclei. It was found that the high-order multipolarity-six (β6) 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 ~190 neutrondeficient nuclei. Triaxiality with γ~30° is found in the ground and excited rotational states of the A ~ 70 germanium isotopes. Octupole correlations have also been discussed in different mass regions. In recent experiments, the textbook nucleus 158Er has been reached at ultrahigh spins around 65ħ . We have studied 158Er 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 γ ≈ 12° triaxial-strongly-deformed (TSD) excited configuration can well reproduce the observed large transitional quadrupole moment. It is demonstrated that the TSD minimum at negative γ deformation which appears in the principal-axis-cranking approach is a saddle point if allowing the rotational axis to change direction. [ABSTRACT FROM AUTHOR]

High-K isomeric states and their decays give access to the excited-state structure of neutron-rich rare-earth nuclides, where a maximum in β6 deformation has been predicted. Using extensions of the Nilsson-Strutinsky approach, including configuration constraints, we have calculated single-particle energies, and two-quasiparticle excitation energies. Their sensitivity to β6 deformation is discussed, as well as the possible influence of β6 deformation on collective rotational energies. [ABSTRACT FROM AUTHOR]

Energy-dependent phenomenological optical model potentials based on a single-folding model approach for the α-12C and deuteron-12C systems were obtained for incident energies between 10 and 100 MeV/nucleon. The Lane-consistent Bruy`eres Jeukenne-Lejeune-Mahaux model nucleon- nucleus potentials were used in these calculations. With only three free parameters, these potentials account satisfactorily for both angular distributions of elastic scattering cross sections and total reaction cross sections of both projectile-target systems within the energy range studied. Comparisons were made between the present potentials and other systematic phenomenological potentials. [ABSTRACT FROM AUTHOR]

Recent high-resolution experiments at JLab give the energy spectra of the hypernuclei , , and. However, their spins and parities of the excited states have not been known experimentally. In the present paper, we make a systematical theoretical investigation for the p-shell hypernuclei, within the shell model based on the nucleon–nucleon (NN) and hyperon–nucleon interactions. The effective NN interaction takes the finite-range density-dependent Gogny force, and the hyperon–nucleon interaction takes an empirical ΛN interaction which includes the ΛN–ΣN and ΣN–ΣN coupling effects. The shell model with the Gogny force without parameters being refitted can reasonably describe both spectra and binding energies of the p-shell nuclei, which gives a confidence for the further calculations of hypernuclei. We compare our results with experimental data as well as various theoretical calculations, and explain the recent experimental hypernuclear spectra observed at JLab. [ABSTRACT FROM AUTHOR]

Gamma rays from the decay of an isomer in 190W116 have been observed following projectile fragmentation of a 1 GeV per nucleon 208Pb beam. An earlier experiment indicated decay from a (10-) isomer to the ground state rotational band. Improved statistics have enabled gamma coincidence and time-difference measurements to be made which alter the previous interpretation. Blocked BCS calculations have also been used together with reduced hindrance factors to indicate possible values of spin-parity for the isomer. [ABSTRACT FROM AUTHOR]