PbWO/sub 4/ scintillators with new avalanche photodiode readout for high-energy physics

The main parameters of large-area avalanche photodiodes (APDs) with a new structure of metal-resistive-semiconductor layers (MRS) are described. The first experimental data taken with a small PbWO/sub 4/ (PWO) electromagnetic calorimeter equipped with a new APD readout system in a 20-70 GeV electron beam at CERN are also presented.