A method has been developed for reconstructing continuous x-ray spectrum based on processing spectrometry information obtained as a result of x-rays scattering on light targets. The reconstruction model takes into account coherent and Compton components of scattered radiation, detector resolution and efficacy. The suggested method is universal: it permits to reconstruct the actual shape of spectrum falling onto the x-ray sample. It should be noted that the initial shape of x-ray spectrum as emitted by the anode of x-ray tube is significantly distorted due to various filters, collimators, including x-ray lenses, scattering processes in the media between the anode and sample. A number of examples is given, where x-ray spectra were reconstructed for different configurations of spectrometry tracts. Thus reconstructed x-ray spectra are further used (as input) for quantitative XRF analysis of samples by the method of fundamental parameters (MFP). The developed calculation code implements the MFP version in the original Sherman interpretation6. As input, both the absolute values of intensities for the base lines of characteristic radiation (in case of 1 00% rating), and relative values of intensities rated by the value of the base lines of a "pure element" are used. The procedure of calculating intensities of the "pure element" base lines based on the analysis of samples with known chemical composition is given. Intensities of the base lines of characteristic radiation are determined through application of the deconvolution procedure by the least-squares method. As basic functions, the following is used: Gauss distributions for characteristic radiation lines and piecewise-linear approximation for the background. The efficiency and universal nature of the above comprehensive method is supported by the results of qualitative RFA obtained for a number of samples with known chemical composition using different types of spectrometers.

No abstract