Determination of k0-factors of short-lived nuclides and application of k0-NAA to selected trace elements

As part of the standardization program of k0-based NAA (k0-NAA) methods at the Dalhousie University SLOWPOKE-2 reactor (DUSR) facility, the k0-factors of 15 analytically important short-lived nuclides (half-life <65 s) were determined with respect to gold (197Au). The elemental standards used were prepared mostly from their primary standard solutions. The samples were irradiated in both inner and outer pneumatic sites of the DUSR facility and counted using an HPGe-detector coupled to an ORTEC’s digital gamma-ray spectrometer. The k0-factors determined using both inner and outer irradiation sites were found to be within ±5% with respect to either recommended or literature values in most cases. The Z-score values at 95% confidence level were found to be in the range of ±0.03–1.6. The k0-NAA method was applied to three different NIST standard reference materials (SRMs) and concentrations of six elements, namely Ag, F, Hf, Rb, Sc, and Se were determined using their short-lived nuclides. The concentrations of these elements were also determined by relative NAA method for comparison purposes.