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The possible existence of stable axial octupole and tetrahedral deformations is investigated in 80Zr and 98Zr. HFBCS calculations with parity projection have been performed for various parametrizations of the Skyrme energy functional. The correlation and excitation energies of negative parity states associated with shape fluctuations have been obtained using the generator coordinate method (GCM). The results indicate that in these nuclei both the axial octupole and tetrahedral deformations are of dynamic character and possess similar characteristics. Various Skyrme forces give consistent results as a function of these two octupole degrees of freedom both at the mean-field level as well as for configuration mixing calculations. [ABSTRACT FROM AUTHOR]

Superfluidity is a generic feature of various quantum systems at low temperatures and it is in particular important for the description of dynamics of low energy nuclear reactions. The Time-Dependent Density Functional Theory (TDDFT) is, to date, the only microscopic method which takes into account in a consistent way far-from-equilibrium dynamics of pairing field and single-particle degrees of freedom. The local version of TDDFT, so-called TDSLDA, is particularly useful for the description of nuclear reactions and is well-suited for leadership class computers of hybrid (CPU+GPU) architecture. The preliminary results obtained for collisions involving both medium-mass and heavy nuclei at the energies around the Coulomb barrier are presented. [ABSTRACT FROM AUTHOR]

A new excitation mode has been predicted to exist in the unitary Fermi gas. It has a form of a spin-polarized impurity, which was dubbed as ferron. It is characterized by a closed nodal surface of the pairing field surrounding a partially spin-polarized superfluid region, where the phase differs by π. In this paper, we discuss the effect of temperature on the generation of the ferron and the adiabaticity of the spin-polarizing potential together with ferron’s ground-state properties. [ABSTRACT FROM AUTHOR]

In recent years, the N = 90 isotones have been investigated to a large extent in relation to studies of quantum phase transitions. In this paper, we use the mean field approach with pairing-deformation self-consistent total Routhian surface (TRS) calculations to study the N = 90 isotones and neighboring nuclei. The important probes, such as moments of inertia, quadrupole moments, the energy ratio of E(4+1)/E(2+1), and octupole and hexadecapole degrees of freedom are considered and the calculated results are compared with the available experimental data. From a microscopic point of view, the N = 90 isotones characterize the onset of the deformed region and are very well described by mean field calculations. The results are compared with those from other studies in beyond mean field approximations. Shape coexistence phenomena in the region of interest are discussed. [ABSTRACT FROM AUTHOR]

A fully symmetry unrestricted time-dependent density functional theory extended to include pairing correlations is used to calculate properties of the isovector giant dipole resonances of the deformed open-shell nuclei 172Yb (axially deformed), 188Os (triaxially deformed), 238U (axially deformed) and to demonstrate good agreement with experimental data on nuclear photo-absorption cross sections for two different Skyrme force parametrizations of the energy density functionals SkP and SLy4. [ABSTRACT FROM AUTHOR]

Within the framework of the unrestricted time-dependent density functional theory, we present for the first time an analysis of the relativistic Coulomb excitation of the heavy deformed open shell nucleus 238U. The approach is based on the superfluid local density approximation formulated on a spatial lattice that can take into account coupling to the continuum, enabling self-consistent studies of superfluid dynamics of any nuclear shape. We compute the energy deposited in the target nucleus as a function of the impact parameter, finding it to be significantly larger than the estimate using the Goldhaber-Teller model. The isovector giant dipole resonance, the dipole pygmy resonance, and giant quadrupole modes are excited during the process. The one-body dissipation of collective dipole modes is shown to lead a damping width Γ↓ ≈ 0.4 MeV and the number of preequilibrium neutrons emitted has been quantified. [ABSTRACT FROM AUTHOR]