AN IMPROVED NUCLEAR MEASURING PRINCIPLE. Quarterly Progress Report No. 3 Covering the Period from December 1, 1959 to March 1, 1960

The scintillation counter has proven to be a very valuable research tool, but urfortunately, its ability to meet necessary stability requirements has restricted its use in industrial applications. Several techniques are being investigated which cancel out reasonable variations in detector sensitivity, resulting in improved stability. The general technique consists of alternately measuring the intensity transmitted through the sample and through a calibrated absorber, and difference in intensity causing the calibrated wedge to re-position itself. A comparison of commutating and noncommutating systems is made and other applications of scintillation counter systems are discussed. (For preceding period see ARF-1152-6.) (W.D.M.