XX Conference { Location, Date-start- Date-end, Year THE TIME-OF-FLIGHT SYSTEM OF THE PAMELA EXPERIMENT

The PAMELA satellite-borne experiment, scheduled to be launched in 2004, is designed to provide a better understanding of the antimatter component of cosmic rays. In the following we report on the features and performances of its scintillator telescope system which will provide the primary experimental trigger and time-of- ight particle identication. 1 Mission overview The PAMELA experiment 1) is a satellite-borne apparatus devoted to the study of cosmic rays, with an emphasis on antiparticles and search for antinuclei. Es-pecially, the instrument will measure the spectra of cosmic rays (protons, elec-trons, corresponding antiparticles and light nuclei) over an energy range and with a statistics unreachable by balloon-borne experiments. The core of the instrument (shown in Fig. 1) is a permanent magnet spectrometer 2) equipped with a double-sided, microstrip silicon tracker. Under the spectrometer lies a sampling electromagnetic calorimeter 3), composed of tungsten absorber plate