[en] The energy resolution and stability of a Van de Graaff accelerator can be substantially improved by reducing the angle between the actual ion-beam trajectory and the ideal axis of the magnetic analyzer system, and by increasing the efficiency of the terminal stabilizer system. For this purpose, the ion-beam is forced to pass through two slits located on the ideal axis of the magnetic analyzer system and a phase-delay filter is added to the terminal stabilizer system. Thus, the energy resolution is improved by a factor 4 and the energy stability by a factor 10

[en] The working conditions of a new on-line electrostatic collection system are presented. The main charactersitics are high efficiency (reaching 20%) and short delay time (down to the millisecond). The salient features of specific devices for measurements of absolute cross sections, recoil range distributions and angular distributions are given

[en] Radioactive studies of light neutron rich exotic nuclei have been performed on the LISE line at GANIL. These isotopes were produced via projectile nuclear fragmentation of 60 MeV/nucleon ⁴⁰Ar on Be. Physical separation of the nucleides was achieved through the Projectile Fragment Isotopic Separation (PFIS) method (magnetic analysis and differential stopping power effects). At least 8 nuclei were observed for the first time through β-γ coincidence measurements (⁴⁰S, ³⁸P, ³⁷P, ³⁶Si, ³⁵Si, ²⁴F, ²²O) as well as already known half-lives to provide a check of the procedure (³⁶P, ³⁰Mg, ³²Al)

[en] We present cross sections, mean projected recoil ranges and angular distributions of radioactive alpha emitters produced in ¹²C-induced reactions at 1 GeV on targets ranging from Gd to Pb. We use a new technique of on-line electrostatic collection. The wide spectrum of produced isotopes corresponds to nuclei close to the target up to nuclei with as much as 60 nucleons less than the target. The intranuclear cascade calculations can reproduce the main features of nuclei having lost up

[en] Environmental protection is essential to the quality of lifer for present and future generations. The EU lines of priorities for reucing the adverse health effects associated with certain environmental factors, include. To prevent risks associated with the facilities at risk in the transmission of certain diseases such as Legionella. (Author)

[en] In the search of a hybrid system (the coupling of the particle accelerator to an under-critical reactor) for radioactive waste transmutation the TARC (Transmutation by Adiabatic Resonance Crossing) program has been developed. One of its purpose is the study of the lead properties for neutronics. In the 'Energy Amplifier' project the lead is used both as neutron source and neutron moderator. The neutronic properties of lead have been determined from the measurement of the energy and the flux of spallation neutrons produced inside a large lead block. The different methods used are described. The strong correlation with time and energy has been measured by detecting the prompt gamma rays emitted from the known resonance of different materials

[en] A new method for the isotopic separation of projectile fragments is exposed. The application to the LISE spectrometer at GANIL provided radioactivity data on light neutron-rich nuclei (mass range 14--40). The observation on ¹⁷B of the beta-delayed four neutron decay mode is reported for the first time

[en] Radioactive studies of light neutron rich exotic nuclei from ¹⁷C to ⁴⁰S have been performed on the LISE line at GANIL. These isotopes were produced via projectile fragmentation of 60 MeV/nucleon ⁴⁰Ar on Be. The adjunction of an energy degrader with appropriate shape is shown to allow the use of the LISE spectrometer for a projectile fragment isotopic separation. At least 9 nuclei were observed for the first time through β-γ coincidence measurements. The predictive power of different models for β decay properties is examined

[en] In the search of hybrid system (the coupling of the particle accelerator to an under-critical reactor) for radioactive waste transmutation the TARC (Transmutation by Adiabatic Resonance Crossing) program has been developed. One of the target of the TARC program is the study of the efficiency of a 'Energy Amplifier' system for nuclear waste incineration. Among the radioactive wastes the most interesting is the fission product ⁹⁹Tc from nuclear plants heaving a half-live of ∼ 10⁵ years. Using a fast rabbit technique and gamma ray spectroscopy, the transmutation rate of ⁹⁹Tc by spallation neutrons inside a large lead block was measured. The data from each 9 s rabbit cycle were stocked by means of an acquisition system based on the CERN CASCADE code especially adapted for gamma spectroscopy and able to catch large amounts of coincidence events. The measurements technique is described and the preliminary results are given. Also, in progress are simulations using new technique for production and propagation of neutrons in lead. Due to the plenty of spallation neutrons the capability of burning certain nuclear wastes is already proved

[en] We have tested a cylindrical large size single-wire chamber to check the possibility of obtaining high precision in the measurement with such detectors of the energy of the particles, dissipated entirely in the gas of the chamber. Such tests were carried out at the same time as preliminary studies of the multiwire systems devoted to measurements of individual energies, multiplicity and angular distributions for particle nuclei, with or without beta emission. The length of the chamber is 1 m, the diameter, 0.2 m and the wire diameter is 100 μm. The composition of the chamber gas is 90% Ar and 10% CH₄. Several measurements were performed with this chamber and the energy spectrum from a 3 α source is given. The FWHM at 5.16 MeV is 76 keV which is a rather good value for a detector of 4 μπ geometrical efficiency. On the basis of these results the project of a 8 wire detector was developed. The simulation of the operation of this chamber was made with the help of GARFIELD code of CERN. It was found that the field in the vicinity of the wire is very homogeneous. The paper presents also the equipotentials at 1 mm distance from the wire center. Also, are shown the gain fluctuations computed for 20 avalanches when the external tube potential and the potential center wire are matched in order to obtain a homogeneous field around the wires