A. Korn

The CDF-II time-of-flight detector

A Time-of-Flight (TOF) detector, based on plastic scintillator and fine-mesh photomultiplier tubes, has been added to the CDF-II experiment. Since August 2001, the TOF system has been fully instrumented and integrated into the CDF-II data acquisition system. The TOF system will provide particle identification of low momentum charged pions, kaons and protons in -collisions. With a design resolution goal of about 100 ps, separation between charged kaons and pions is expected at the 2 sigma level for momenta below 1.6 GeV/c, which enhances CDFs b-flavor tagging capabilities. They describe the design of the TOF detector and discuss its on-line and off-line calibration. Some performance benchmarks using proton-antiproton collision data are presented.

The CDF time of flight detector

A new Time of Flight (TOF) detector based on scintillator bars with fine-mesh photomultipliers at both ends has been in operation since 2001 in the CDF experiment. With a design resolution of 100 ps, the TOF can provide separation between K/sup /spl plusmn// and /spl pi//sup /spl plusmn// in pp~ collisions at the 2/spl sigma/ level for low momentum, which enhances b flavor tagging capabilities. Because of its very fast response, the TOF is an excellent triggering device, and it is used to trigger on highly ionizing particles, multiple minimum ionizing particles and cosmic rays. Particle identification is achieved by comparing the time-of-flight of the particle measured by the TOF to the time expected for a given mass hypothesis. In order to obtain the resolution necessary for particle ID, optimal calibrations are critical. This paper describes the TOF detector, its calibration procedure, the achieved resolution, the long term operation performances and some of the first results from data analysis using this detector.