Development of a Method to Correct for Coincidence Losses in High Count Rate Gamma-ray Spectrometry

Abstract

A correction method for coincidence losses due to both analyser dead-time and pulse pile-up in gamma-ray spectrometry has been developed. The method involves the simultaneous measurement of the fractional dead-time, DT, of the analogue-to-digital converter (ADC), and the logic pulse rate, R₈, at the "SCA OUT" (single channel analyser output) of the ADC as time dependent quantities, using a multichannel scaler. This correction method has been successfully applied to rapidly varying count rates (with initial dead-time over 50%) of nuclides with half-lives as short as a fraction of a second.