Large Scintillators as Threshold Detectors for High-Energy Processes

Abstract

The design is described of several liquid organic scintillation counters which have been used to detect 100-Mev neutrons and gamma rays with the exclusion of lower-energy particles and quanta. The neutron counter efficiency is a few percent and is nondirectional, properties not possessed by a more conventional counter telescope system. The gamma-ray counter has an efficiency of about 50%, with a line width of about 10%. Particular problems arise in the use of these counters; counting rate stability is difficult to achieve; the maximum counting rate is limited by the pileup of individual pulses due to their finite width. These problems are discussed in detail and some solutions mentioned.