Accession Number : AD0721518

Title :   Investigation of Source-Dependent Contributions to Photomultiplier Noise,

Corporate Author : DEFENCE RESEARCH ESTABLISHMENT OTTAWA (ONTARIO)

Personal Author(s) : Johnson,F. A.

Report Date : 09 JUN 1970

Pagination or Media Count : 7

Abstract : Fast pulses produced at the output of a photomultiplier as a result of the interaction of low-energy gamma-rays in the glass faceplate are shown to have similar characteristics to those due to Cerenkov events generated there by high-energy gamma-rays. In both cases the pulses can be distinguished from those produced by gamma-ray interactions in a scintillator which is viewed by the photomultiplier. On the basis of fast-crossover-timing and pulse-height-distribution measurements it is concluded that visible light, produced in the glass faceplate by the low-energy gamma-rays, is responsible for the pulses observed. Other mechanisms by which similar pulses could be produced by low-energy gamma-rays are also considered, but separate identification would appear to be difficult. (Author)

Descriptors :   (*PHOTOMULTIPLIER TUBES, NOISE(RADIO)), (*CERENKOV RADIATION, GAMMA RAYS), SCINTILLATION COUNTERS, GAMMA RAY SPECTRA, ELECTRONS, PULSE HEIGHT ANALYZERS, INTERACTIONS, CANADA

Subject Categories : Electrical and Electronic Equipment
      Nuclear Instrumentation

Distribution Statement : APPROVED FOR PUBLIC RELEASE