Advantages and Disadvantages of Bayesian Methods for Obtaining Xrf Net Intensities

A method of extracting net intensities for the element peaks in an X-ray fluorescence (XRF) spectrum based on Bayes Theorem will be reviewed and discussed. The method has several advantages, among them that the total counts are preserved and that the a priori information is incorporated in a natural manner. These make it, for example, less sensitive to errors in the peak position, widths, and alpha/beta ratios. However, there are also disadvantages. The preservation of total counts means that spurious peaks, such as those from crystallite diffraction, will have their counts included in one or more of the element peaks. We present the results of applying a Bayesian deconvolution method to several XRF spectra and compare them to conventional methods. The spectra are selected to illustrate both the advantages and disadvantages of this method. Errors introduced by variations in the functions used to model the peak shapes are investigated. Quantitative comparisons are also made by using the net intensities from each method in standardless analysis.