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Investigations into the role of the N/Z ratio on the decay modes of compound nuclei are presented. Characteristics of fragments with atomic number 6<=Z<=28 and light charged particles emitted in 78,82Kr+40Ca at 5.5 MeV/A reactions were measured at the GANIL facility using the 4π-INDRA array. Data are compatible with an emission process from a compound nucleus. Persistence of structure effects and emission before full separation of fission fragments are evidenced from elemental cross-sections and coincidence data between light charged particles and fragments. Data are discussed in the framework of the transition state model. [ABSTRACT FROM AUTHOR]

The blocking technique in single crystals is a direct method to investigate the presence of long fission time components. With a lead beam impinging on a germanium single crystal, we tried to produce compound nuclei (CN) with atomic number Z = 114 at high excitation energy. Blocking patterns for reaction products are reconstructed with position sensitive detectors at 20 ° relative to the beam direction. The Z and the energies of all products are measured with ΔE-E telescopes of the 4π INDRA array, so that all reaction channels are unambiguously identified. With this setup, we can reach long fission times (>10-18 s) that can be associated with CN fissions. However, in contrast to previous experiments in which such long fission times could be measured for Z = 120 and 124, no hint of long lifetimes within our sensitivity limit for Z = 114 was observed, which may be due to the neutron deficiency of the formed isotopes. [ABSTRACT FROM AUTHOR]

This report summarizes the experiments relative to Super-Heavy Element studies done at GANIL — CEA — CNRS since 1999. It also gives an overview of future experiments and opportunities offered by SPIRAL 2 and LINAG beams in a medium term.. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

We performed an experiment to search for a signature of a long living component in the collision of 238U + 238U between 6.09 and 7.35A MeV. The experiment was performed at GANIL using the spectrometer VAMOS, tuned for observing reactions with kinematics similar to fusion-fission events. Theoretical calculations indicate that if a long living component would exist for this reaction, the most probable fission channel of such a giant system would be via the emission of quasi-lead nuclei. We detected events of such a category in the focal plane of VAMOS. These events present an excitation function growing as a function of the bombarding energy. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

Fission time measurements have been undertaken in the super-heavy elements domain around Z=120, using the crystal blocking technique. Complete fusion followed by fission mechanisms have been evidenced from time measurements and detailed kinematics analysis. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

27Ne has been investigated through the one neutron transfer reaction 26Ne(d,p)27Ne in inverse kinematics at 9.7 MeV/nucleon. The results support the existence of a low lying negative parity state in 27Ne which is a signature of a reduced sd-fp shell gap in the N=16 neutron rich region, at variance with stable nuclei. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

The emission of intermediate-mass fragments in collisions of [sup 197]Au on [sup 197]Au was systematically studied over the range of incident energies from 40 to 150 A MeV using the 4π-multidetector INDRA and beams from the heavy-ion synchrotron SIS at GSI Darmstadt. The analysis was performed as a function of incident energy and of impact parameter, defined through the total transverse energy of light charged particles (Etrans 12, Z≤2). This observable was found to scale linearly with the collision energy up to a certain limit above which it saturates. Strong forward-backward asymmetries in the emission pattern with respect to the rapidities of the projectile and target residua were observed. Their possible relation to equilibration is discussed and interpreted in the framework of molecular dynamics and statistical multifragmentation models. Transverse velocities at midrapidity for peripheral collisions were found to show a surprisingly weak dependence on the incident energy. On the contrary, transverse velocities at midrapidity for central collisions showed a strong dependence on incident energy indicating an increasing importance of collective flow with increasing bombarding energy. © 2002 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The influence of radial flow on nuclear multifragmentation is studied using Au+Au central collisions for incident energies between 40 and 100 MeV/A. Central collisions are selected via an impact parameter estimator defined by the transverse energy of light charged particles. At all energies, the fragment size distributions are studied using the Statistical Multifragmentation Model (SMM) in order to extract thermal excitation energies. The excess kinetic energies are analyzed via the hypothesis of a radial, self-similar, but non-isotropic flow. At the lowest energy, this flow is small with respect to the thermal energy whereas, at 100 MeV/A thermal and radial energies are of the same order. The nature and origin of the radial flow is discussed. A comparison with the predictions of the Quantum Molecular Dynamics code is presented. © 2002 American Institute of Physics. [ABSTRACT FROM AUTHOR]

A long-term new experimental program has begun at GANIL, i.e. search for new super heavy nuclei and their structure. The first part consists in studying the structure of the [sup 273]110 isotope which involves the development of high intensity Se beam. In parallel, reactions involving Inverse Kinematics will be studied allowing to have a versatileness set-up. By adding germanium and electron detectors, spectroscopic studies could be made on trans-fermium elements. Preliminary results showed that the Wien Filter has a suppression of the incident beam with a 10[sup 10] factor, which is comparable with results elsewhere. We show recent results with the present set-up at GANIL in producing Fr isotopes in the Kr + Sb reaction. We present also the result of our Kr + Pb experiment, which tried to reproduce the Berkeley result of the element 118. [ABSTRACT FROM AUTHOR]