A. Genoux-Lubain

Bio: A. Genoux-Lubain is an academic researcher from Centre national de la recherche scientifique. The author has contributed to research in topics: Fission & Excited state. The author has an hindex of 9, co-authored 17 publications receiving 262 citations.

“DELF”, a large solid angle detection system for heavy fragments

Abstract: To detect the heavy fragments (Z > 8) emitted at large angle (30° < θ < 150°) in heavy ion collisions at GANIL, a large solid angle detection system has been built It consists of 18 independent cells surrounding the target, the beam axis being the revolution axis In each cell, a fragment penetrates at first into a parallel plate avalanche counter with localization which gives velocity, position and ∂E∂x measurements and then into an ionization chamber with longitudinal field for the residual energy measurement The Z evaluation is performed over a large range of velocities (005 < EA < 5 MeV/u) for atomic numbers ranging from 8 to 90

Temperature in non-equilibrium states: a review of open problems and current proposals

Abstract: The conceptual problems arising in the definition and measurement of temperature in non-equilibrium states are discussed in this paper in situations where the local-equilibrium hypothesis is no longer satisfactory. This is a necessary and urgent discussion because of the increasing interest in thermodynamic theories beyond local equilibrium, in computer simulations, in non-linear statistical mechanics, in new experiments, and in technological applications of nanoscale systems and material sciences. First, we briefly review the concept of temperature from the perspectives of equilibrium thermodynamics and statistical mechanics. Afterwards, we explore which of the equilibrium concepts may be extrapolated beyond local equilibrium and which of them should be modified, then we review several attempts to define temperature in non-equilibrium situations from macroscopic and microscopic bases. A wide review of proposals is offered on effective non-equilibrium temperatures and their application to ideal and real gases, electromagnetic radiation, nuclear collisions, granular systems, glasses, sheared fluids, amorphous semiconductors and turbulent fluids. The consistency between the different relativistic transformation laws for temperature is discussed in the new light gained from this perspective. A wide bibliography is provided in order to foster further research in this field.

Dynamics of nuclear fission

Abstract: The most interesting process of collective flow of nuclear matter is the fission process. The time-scale of this process at moderate to high excitation energies is reviewed. Various methods to measure the time associated with large scale collective flow of nuclei in the range of 10^(-21) to 10^(-17) s are compared. Pre- and post-scission multiplicities of light particles in particular neutrons are shown to be a sensitive probe of the dynamics of nuclear fission. A systematics of pre- and post-scission neutron multiplicities associated with nuclear fission is presented. The magnitude of nuclear dissipation deduced from pre- and post-scission neutron multiplicities is compared with theoretical estimates.

INDRA, a 4π charged product detection array at GANIL

Abstract: INDRA, a new and innovative highly segmented detector for light charged particles and fragments is described. It covers geometrically 90% of the 4π solid angle and has very low detection thresholds. The detector, operated under vacuum, is axially symmetric and segmented in 336 independent cells allowing efficient detection of high multiplicity events. Nucleus identification down to very low energy threshold (≈ 1 A MeV) is achieved by using ionization chambers operated with low pressure C 3 F 8 gas. Residual energies are measured by a combination of silicon (300 μm thick) and cesium iodide (5 to 14 cm in length) detectors. Very forward angles are covered by fast counting phoswich scintillators (NE102/NE115). Charge resolution up to Z = 50 is achieved on a large energy dynamic range (5000 to 1 for silicon detectors). Isotopic separation is obtained up to Z = 3. The treatment of the signals is performed through specifically designed and highly integrated modules, most of which are in the new VXIbus standard. Full remote control of parameter settings, including visualization of signals, is thus allowed. The detector is continuously monitored with a laser source and electronic pulsers and is found stable over several days. Energy calibration procedures, making use of specific detectors and the ability of the GANIL accelerator to deliver secondary beams, have been developed. First experiments were performed in the spring of 1993.