Semi‐empirical schemes for x‐ray attenuation coefficients in the context of PIXE

Various semi‐empirical schemes for generating x‐ray attenuation coefficients, μ/ρ, devised primarily for use in electron probe microanalysis, are considered for application in the PIXE analysis of thick specimens where the relevant x‐ray energy region is 1–40 keV. Using selected high‐accuracy experimental data, it is shown that current theoretical values of μ/ρ agree better with the data than do the various schemes. The errors transmitted into PIXE analysis by use of the theoretical values are estimated, and a new parameterization of these values suitable for microcomputer use is justified and tested.