Excitation of low-Z fluorescence by radiation from thin-window X-ray tubes

The intensities of X-ray fluorescence and its components for primary radiation of the tubes with the window thickness 300 μm (grounded anode) and 75 μm (grounded cathode) have been compared for the elements with low atomic numbers. A significant increase of total intensity causes slight changes in the contribution of photo- and Auger electrons to its formation, when using the X-ray tube with grounded cathode. However it is still necessary to consider this contribution in computational modeling of long-wavelength characteristic radiation. The experimental results agree well with the calculations of X-ray carbon fluorescence intensity, which were based on the ionization of its atoms by photo- and Auger electrons.