Measurement of the Number of Photoelectrons per MeV for Neutron Detectors

Abstract

The light gains of a detector system (PMT and scintillator) is characterized by the number of photoelectrons produced per unit of energy (usually MeV). In this study, the results of light gain tests for 10 Hamamatsu R11833 model photomultiplier tubes (PMT) are shown. Various radioactive sources were used in conjunction with the EJ309 liquid scintillator to determine the light gain. The number of photoelectrons produced per unit energy was determined by comparing the size of the signal generated by the photons produced by PMT during the scintillation process using radioactive sources and the size of the signal generated when a single photo electron (SPE) was produced by the PMT. The test results show that the performances of the PMTs are sufficient for neutron detector arrays used in experiments with radioactive ion beams. The supply voltage of the photomultiplier tubes must be changed to achieve similar light gains.

Keywords

• Photomultiplier Tube
• Single Photoelectron
• Liquid Scintillator
• Photoelectron Yield
• Neutron Detection.

References

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