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In the first part of this paper we recall a recent study concerning low energy fission dynamics. Propagation is made by use of the Time Dependent Generator Coordinate Method, where the basis states are taken from self-consistent Hartree-Fock-Bogoliubov calculations with the Gogny force. Theoretical fragment mass distributions are presented and compared with the evaluation made by Wahl. In the second part of this paper, new results concerning scission configurations are shown. Deviations of the fission fragment proton numbers from the Unchanged Charge Distribution prescription and fission fragment deformations are discussed. © 2005 American Institute of Physics [ABSTRACT FROM AUTHOR]

Recent microscopic studies devoted to fission are presented. First, potential energy surface properties are extracted using the Hartree-Fock-Bogoliubov theory with constraints. Then, dynamical properties of the fission process are studied by use of the time-dependent Generator Coordinate Method based on self-consistent intrinsic nuclear wave functions calculated with the Gogny force. The influence of fission dynamics on fragment mass distributions is discussed. © 2005 American Institute of Physics [ABSTRACT FROM AUTHOR]

We discuss the uniqueness of often proposed experimental signatures for quark matter formation in relativistic heavy ion collisions, using insight gained from non-equilibrium models (three-fluid hydrodynamics and the hadronic transport model UrQMD). It is demonstrated that these two models — although they do treat the most interesting early phase of the collisions quite differently (thermalizing QGP vs. coherent color fields with virtual particles) both yield a reasonable agreement with a large variety of the available heavy ion data. Hadron/hyperon yields, including J/Ψ meson production/suppression, strange matter formation, dileptons, and directed flow (bounce-off and squeeze-out) are investigated. Observations of interesting phenomena in dense matter are reported. However, we emphasize the need for systematic furore measurements to search for simultaneous irregularities in the excitation functions of several observables in order to come close to pinning the properties of hot, dense QCD matter from data. [ABSTRACT FROM AUTHOR]

Potential energy surfaces are calculated in the elongation-asymmetry plane, with nuclear shapes ranging from sphericity to very large deformations, using the Hartree-Fock-Bogoliubov method and the Gogny nucleon-nucleon effective interaction (parameterization D1S), for the 226Th and 256,258,260Fm Fissioning systems. In order to discriminate between pre- and post-scission configurations, we define a criterion based on the nuclear density. Using this criterion, a big number of scission configurations are identified, and several fragment properties are extracted from them, namely fragment deformations, deformation energies, energy partitioning, neutron binding energies at scission, charge polarization, total fragment kinetic energies and neutron emission multiplicities. [ABSTRACT FROM AUTHOR]

Properties of 226Th, 256Fm, 258Fm and 260Fm nuclei in the scission region are described using a full-microscopic Hartree-Fock-Bogoliubov approach with the effective Gogny nucleon-nucleon interaction. In a first step, the Potential Energy Surfaces are computed in the (q 20, q30) plane, the scission lines are found, fulfilling a given criterion on the density in the nuclear neck. Finally a few properties of the fragments along this line are presented. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

In this work we discuss the multiparticle-multihole configuration mixing method which aims to describe the structure of atomic nuclei. Based on a variational principle it is able to treat in a unified way all types of long-range correlations between nucleons, without introducing symmetry breaking. The formalism is presented along with some preliminary results obtained for a few sd-shell nuclei. In the presented applications, the D1S Gogny force has been used. [ABSTRACT FROM AUTHOR]

We study spatial properties induced by pairing correlations, within the HFB approach employing the finite range D1S Gogny interaction. Local and non-local quantities, such as pairing tensor, are discussed as well as the coherence length. We show that a generic feature occurs at the surface of nuclei, namely Cooper pair of small size characterized by a coherence length ξ∼2 fm. [ABSTRACT FROM AUTHOR]

We analyze the surface geometry of the spherical even-even Ca, Ni, Sn and Pb nuclei using two approaches: The relativistic Dirac-Hartree-Bogoliubov one with several parameter sets and the non-relativistic Hartree-Fock-Bogoliubov one with the Gogny force. The proton and neutron density distributions are fitted to two-parameter Fermi density distributions to obtain the half-density radii and diffuseness parameters. Those parameters allow us to determine the nature of the neutron skins predicted by the models. The calculations are compared with existing experimental data. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]