Abstract
The instrumental neutron activation analysis (INAA) method was combined with the gamma - gamma coincidence technique to measure Iron (Fe) and Terbium (Tb) concentrations in geological (Montana II Soil) and environmental (Coal Fly Ash) standard materials. The measured concentrations, which agree well with the corresponding certified values, are compared with those obtained from the traditional INAA method. It is demonstrated that employing the gamma - gamma coincidence technique slightly improves the accuracy of the analysis. Furthermore, the coincidence technique enhances the detection limits of Tb by similar to 4.5 and similar to 5.5 times in environmental and geological samples, respectively, but has almost no enhancement in those of Fe. The gamma - gamma coincidence technique therefore does not always promote the analysis quality of the INAA method, but it is effective for analyzing elements whose characteristic gamma rays sustain a high Compton background and/or are overlapped with other gamma rays.