The time-of-flight TOFW detector of the HARP experiment: Construction and performance

The construction and performance of a large area scintillator-based time-of-flight detector for the HARP experiment at CERN are reported. An intrinsic counter time resolution of similar to 160 ps was achieved. The precision on the time calibration and monitoring of the detector was maintained at better than 100 ps by using dedicated cosmic rays runs, a fast laser-based system and calibrations with beam particles. The detector was operated on the T9 PS beamline during 2001 and 2002. A time-of-flight resolution of similar to 200 ps was obtained, providing pi/p discrimination at more than 3sigma up to 4.0 GeV/c momentum.