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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]

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]

Angular and energy distributions of negative secondary ions Aun (n = 2 – 7) emitted from gold targets by gold cluster projectiles Au4 and Au9 at 200 keV per atom have been measured. A 256-anodes channel plate based detector for simultaneous detection in time of flight measurements was used. It is shown that angular distributions are rotationally symmetric with respect to the surface normal .They depend on the ejection energy. The energy spectra of the different emitted ions have similar shapes with almost the same mean energy. Energy spectra are satisfactorily reproduced by a spike-like model. © 2003 American Institute of Physics [ABSTRACT FROM AUTHOR]