ALICE T0 detector

Fast timing and trigger detector T0 for the ALICE experiment at CERN LHC is described. Performance of T0 prototype measured with a mixture of 6 GeV/c negative pions and kaons is given. The best time resolution (28 ps r.m.s.) was reached with radiator diameter matching that of the photo cathode. The results for all the tested radiator sizes are considerably better than 50 ps - the baseline requirement for ALICE experiment.