A 5 ps TOF-counter with an MCP–PMT

We measured the timing resolution of TOF counters by means of Cherenkov-light detection with a Micro-Channel Plate Photo-Multiplier Tube, and attained σTOF=6.2ps using 3GeV/c pion-beams with a readout electronics of 4.1 ps resolution. The optimum radiator thickness was examined and the detectable number of photo-electrons was analyzed.