Fundamental studies on improvement of count rate performance of scintillation detectors

The purpose of this article is to introduce fundamental studies on improvement of count rate performance of scintillation detectors which Dr. Eiichi Tanaka dedicated himself to carrying out. He proposed a new technique based on the combination of pulse shortening and selective integration in which the integration period is not fixed but shortened by the arrival of the following pulse. Theoretical analysis of the degradation of the statistical component of resolution is made for the proposed system with delay line pulse shortening, and the factor of resolution loss is formulated as a function of the input pulse rate. A new method is also presented for determining the statistical component of resolution separately from the non-statistical system resolution. Preliminary experiments with a NaI(Tl) detector had been carried out, the results of which are consistent with the theoretical prediction. The related works are also introduced. (author)