Noise sources in the C31000D photomultiplier

Abstract

The peaked pulse height distribution obtained from those photomultipliers with a gallium phosphide first dynode has enabled the output noise pulses to be accurately classified in terms of their amplitude distributions. The sources contributing to each class could be separated, and in many cases identified, by observing their behaviour when either the temperature or the voltage distribution across the tube was altered. The relevance of these results is discussed with reference to some typical uses of photomultipliers.