Abstract
The Threshold Imaging Cherenkov (TIC) was built as part of an upgrade programme for the NA44 spectrometer in view of 160 GeV·A lead-ion beams from the CERN SPS. The detector is used to distinguish pion tracks from those of heavier particles (K, p, d) in the momentum range of 4-8 GeV/c. Cherenkov photons produced by pions in a 1 m long isobutane radiator are converted to electrons in TMAE at 25°C and detected in a MWPC with 2-dimensional cathode pad readout. A threshold is set on the number of pads hit within a fiducial zone on the cathode plane around a projected external track.