Identification of heavy nuclei by combination of magnetic analysis time of flight and energy measurements

The addition of a time of flight measurement to a Delta E-E telescope set up in the focal plane of a magnetic spectrometer improves the identification of very heavy ions. The Delta E silicon detector is 8 mu thick. The time of flight is measured between a thin plastic scintillator at the entrance of the spectrometer and the Delta E detector, which gives a flight path of 3 m. In order to compensate for the different lengths of the trajectories, the plastic is bent at 15 degrees along the mean trajectory. In these conditions, one has obtained a time resolution of 0.7 ns with a solid angle of 1.8 10/sup -3/ sr (horizontal 2 degrees , vertical 3 degrees ). In these conditions, preliminary results already give an unambiguous identification up to mass approximately=100.