Test of a rich-prototype detector with solid photocathode for hades

The development of a Ring Imaging CHerenkov (RICH) detector working in an environment of strong hadronic background is needed for the High Acceptance Di-Electron Spectrometer (HADES). To get information about the charged particle background situation, a CERN RICH prototype with solid (CsI) photocathode was tested in a 1×A GeV U+Pb reaction at GSI. Also the quantum efficiency of the CsI photocathode was determined to be 10% at 175 nm.Presented at the International School-Workshop Relativistic Heavy-Ion Physics, Prague (Czech Republic), 19–23 September 1994.For the HADES Collaboration (IOP Bratislava, Univ. Clermont-Ferrand, GSI Darmstadt, Univ. Frankfurt, Univ. Gießen, Univ. Kraków, Univ. Milano, ITEP Moscow, LPI Moscow, MEPI Moscow, TU München, Univ. Nikosia, NPI e, Univ. Valencia).We would like to thank F. Piuz for providing the detector and A. Braem for the production of the CsI photocathode. We are also grateful to the accelerator crew at GSI for the stable beam and the Gießen crew W. Döring, A. Rühl and J. Schneider for support.This work was supported in part by BMFT under contract No. 06 GI 475 I(3) and by GSI.