The feasibility of utilizing the64Cu annihilation 511 keV line in INAA

This work demonstrates that the⁶⁴Cu 511 keV line can be used in INAA to determine trace amounts of Cu in biological and environmental materials. The method to reduce the serious interference in γ-ray spectroscopy from nuclides having high energy γ-rays is discussed. A simple INAA procedure is proposed and examined for 7 different SRM materials. An accuracy and precision better than 3% are achieved for tested samples with Na-to-Cu content ratio less than 1000. The minimum detectable Cu concentrations of less than several ppm are calculated for all the analysed samples. To retain the multi-element capability, the k₀-and the modified monostandard methods are applied by using the⁶⁴Cu 511 keV line as the comparator. With the aid of the program MULTINAA, maximum 32 elements are simultaneously determined with an accuracy better than 5% for most elements.