Measurement of photomultiplier effective quantum efficiency
The Joint European Torus (JET) divertor light detection and ranging (LIDAR) system, KE9D, is being modified to perform measurements of plasma edge electron temperature and density in the new gas-box divertor configuration. The change involves raising the line of sight from the divertor region so that the laser beam passes through the plasma edge reaching a depth of approximately 5 cm inside the boundary. Changes are also being made to the detection system. This currently employs a grating spectrometer and a streak camera. The new system will contain a 4-channel filter spectrometer with microchannel plate (MCP) photomultipliers. An important parameter determining the quality of the signal from a photomultiplier is its effective quantum efficiency, calculated from the observed signal and noise characteristics. This parameter has been measured at JET for three commercial photomultipliers with a view to selecting a detector for the new KE9D system. The measurement is described in this paper and results for the three detectors are given.
Bibliographic Reference: Report: JET-R(98)06 EN (1998) 5pp.
Availability: Available from the Publications Officer, JET Joint Undertaking, Abingdon, Oxon, OX14 3EA (GB)
Record Number: 199811100 / Last updated on: 1998-09-28
Original language: en
Available languages: en