PERFORMANCE STUDIES OF LEAD SCINTILLATING-FIBER CALORIMETERS IN THE 1TO 10 GEV RANGE

Three calorimeter modules made of scintillating fibres embedded in a l ead matrix were tested at the CERN Proton Synchrotron. The linearity o f the energy response to electron-induced showers, measured in a modul e having a lead-to-fibre volume ratio of 1.8, is verified within 2.5% whilst the energy resolution is found to be 9.6%/square-root E + 1% at 6-degrees and 4-degrees impact angles in the horizontal and vertical planes. An impact position resolution of 1.51 mm/square-root E + 1.45 mm is achieved. The e/pi+/- separation based on the longitudinal and t ransverse shower size is discussed for various calorimeter configurati ons. Requiring an energy above a threshold of 3 GeV leads to a pi+/- r ejection factor of 12 to 36 with longitudinal criterium, and a pi+/- r ejection factor of 43 to 100 with a transverse cut in a pi+/- energy r ange of 3 to 7 GeV. A combination of both criteria leads to a rejectio n factor between 116 and 303 in the same energy range. The study of th e time shape of the signals shows a very small intrinsic jitter of 0.4 ns on the calorimeter signals. It does not show any evidence of a det ectable neutronic tail in pi+/- signals.