THE USE OF SOURCES EMITTING COINCIDENT GAMMA-RAYS FOR DETERMINATION OF ABSOLUTE EFFICIENCY CURVES OF HIGHLY EFFICIENT GE DETECTORS

The effects of coincidence summing in gamma-ray spectrometry were used in a novel method to obtain absolute photopeak and total efficiency curves of efficient Ge detectors. Without precise knowledge of source activity, both curves were obtained from a single Br-82 spectrum. The efficiency curves were tested by computation and experimental verification of the gamma-ray spectrum of Eu-152. The method makes it possible to calibrate efficient Ge detectors in any counting geometry without the use of calibrated sources. As a result, the feasibility of the use of well-type detectors for single comparator INAA is greatly enhanced.