Performance Studies of Photomutipliers Having Dynodes with GaP(Cs) Secondary Emitting Surface

Characteristics of photomultipliers having dynodes with cesium-activated gallium phosphide secondary emitting surfaces have been investigated. We present measurements of characteristics, generally not available from manufacturers data sheets, for several 8850´s, C70133B´s, 8852´s, and C31024´s. The transit-time difference, the single-electron transit-time spread, and the collection and quantum efficiency uniformity as a function of the position of the photocathode sensing area are measured and discussed. Measurement techniques and descriptions of measuring systems are given in detail. Ephasis is put on the determination of optinum photamultiplier operating conditions, particularly concerning the collection efficiency, and minimum transit-time spread.