Key points are not available for this paper at this time.
A simple fast neutron detector suitable for health physics applications has been constructed using two 931A photo-multiplier tubes in coincidence to reduce background. A ``sandwich'' made of Lucite and activated zinc sulfide is used to produce the scintillations. The efficiency of the instrument for fast neutrons from a Ra–Be source is 1.5±50 percent×10−4. It detects a fast neutron flux of 20 neutrons/cm2 sec. with a counting rate that is over ten times background.
Moulton et al. (1949) studied this question.