Beam tests of a MWPC with CsI photocathode for Cherenkov ring imaging

A 25/spl times/25 cm/sup 2/ asymmetric multiwire proportional chamber, with 7.5/spl times/7.5 mm/sup 2/ photosensitive CsI pads, has been tested with Cherenkov radiation of 3 GeV/c electrons in the T24 test beam at DESY. The performance of the chamber with specially designed low-noise, charge-sensitive preamplifiers is described. The parameters of the CsI-MWPC are compared to those of a TMAE photon detector in order to evaluate their potential as ring imaging Cherenkov (RICH) counters for the HERA-B experiment at DESY. >