RAPID ANALYSIS OF RADIONUCLIDE COMPOSITION (SCREENING) OF LIQUID SAMPLES VIA DECONVOLUTION OF THEIR LS SPECTRA

ABSTRACT. Liquid scintillation (LS) spectrometry based on an original method for processing initial LS spectra is pre-sented. The algorithm used is based on the modeling of spectra transformed by a convolution into group form by the super-position of individual reference spectra taken from a previously created nuclide library. In this library, for each radionuclide (or radionuclide + DP), there is a set of at least 10 spectra measured at different quenching parameters. The model spectrum is presented as a sum of elemental spectra with weight coefficients (cj) that are adjusted during the modeling procedure so that the model spectrum will coincide with the sample spectrum to a maximum degree. Due to the development of new approaches for interpreting LS spectra realized in the software RadSpectraDec, the possibilities of this method for implementing a rapid analysis (screening) of samples with unknown radionuclide composition has been considerably extended. The software now allows us to analyze actual complex radionuclide mixtures of environmental or technological origin. The reliability of the pro-posed procedures has been confirmed by “added-measured ” tests, comparative radiochemical analysis, and by analyzing materials with a regulated content of radionuclides (IAEA, RM, and PT). In this work, data are presented that have been obtained with the given approach for analyzing different materials, such as liquid waste, drill water, liquid discharge, potable water, etc. The limitations regarding sample screening operations are considered as well