An analytical algorithm for calculation of spectral distributions of x‐ray tubes for quantitative x‐ray fluorescence analysis

Abstract

Abstract Fundamental parameter methods for quantitative x‐ray fluorescence analysis require a knowledge of the spectral distributions of x‐ray tubes used for sample excitation. The theoretical models for the calculation of the spectral distributions include a number of parameters which are not known with sufficient accuracy. Also, spectral distributions have been measured for only a few x‐ray tubes operated at 45–50 kV. We have developed an algorithm for calculating x‐ray tube spectral distributions by utilizing extensive electron microprobe data obtained under various operating conditions with a Si(Li) detector. The algorithm includes the calculation of the continuum and the ratio of the characteristic line(s) to the underlying continuum intensity at the wavelength of the characteristic line(s).