AN IMPROVED COINCIDENCE COUNTING TECHNIQUE FOR STANDARDIZATION OF RADIONUCLIDES

A data acquisition system based on a coincidence controller with buffe r memory has been developed for standardization of radionuclides. The energy and output time of the shaped linear pulses generated from an A DC are digitized and latched by a 10 MHz clock oscillator then these d ata are stored in the random access memory (RAM) of the coincidence co ntroller. The coincidence resolving time and gamma windows can be sele cted by an off-line computer analysis program and the efficiency funct ion is obtained by a computer discrimination method. This method is we ll suited for absolute activity measurement of radionuclides with rela tively long-lived intermediate states as well as prompt decay. (C) 199 8 Elsevier Science Ltd. All rights reserved.