Simulation of electron-excited X-ray spectra with NIST-NIH Desktop Spectrum Analyzer (DTSA)

Desktop Spectrum Analyzer (DTSA) is a comprehensive software platform for the collection, simulation, processing, qualitative, and quantitative analysis of electron-excited X-ray spectra. Spectrum simulation is based upon solving the rigorous expression for inner shell ionization, integrated from the incident beam energy to the critical excitation energy, taking into account energy loss of the primary electrons and the loss of ionization power due to electron backscattering. The user can choose from a wide range of cross sections for K-, L- and M-shell ionization, as well as for the X-ray continuum. Both energy-dispersive and wavelength-dispersive spectrometers can be simulated. The simulated spectrum can be inspected at each stage of its generation, propagation through the specimen, propagation through the detector windows and structure, and after application of the detector-broadening function. The final spectrum is calculated on an absolute dose and spectrometer efficiency basis, permitting comparison to experimentally measured spectra. Correspondence for K-shell intensity within +/- 20% relative to experimental values can be achieved over a wide range of photon energy. Appropriate counting statistics can be applied to the simulated spectra, enabling the user to test the accuracy of peak fitting with multiple linear least squares or sequential simplex nonlinear procedures. Published in 2005 by John Wiley & Sons, Ltd.