Results from the measurements of absolute L-shell x-ray production cross sections of In (Z = 49) and Sn (Z = 50) by the impact of electrons with energies in the range of 6–28 keV are presented. The experimental setup has been improved and thin films with thick aluminum substrates were used as targets in the experiments. The effect of directional and energy spreads of the incident electron beam within the films and the characteristic x-ray enhancement due to backscattered electrons and bremsstrahlung photons generated from the substrates were corrected by means of Monte Carlo simulations. The experimental results of In and Sn elements by electron and positron impacts were compared with the DWBA and PWBA-C-Ex theories. It was shown that the L-shell x-ray production cross sections of In and Sn elements by electron impact measured in this paper were in good agreement with the theoretical predictions within the uncertainties and that the discrepancies existed between the experimental results by positron impact, available in the literature, and the theoretical values. The influence of the atomic relaxation parameters (fluorescence yields and Coster–Kronig coefficients) has also been discussed.
Bremsstrahlung spectra generated by electrons with incident energies of 5–25 keV bombarding thick targets of , and are measured with high accuracy. Comparing the experimental spectra with the simulated spectra obtained from the Monte Carlo code penelope, it is found that they are in excellent agreement. The penelope code contains only the cross sections for ordinary bremsstrahlung, while disregarding polarization bremsstrahlung. The results quite definitely indicate that there is no polarization bremsstrahlung contribution to the x-ray radiation spectra produced by incident electrons with thick solid targets for the x-ray energies of interest in this paper ().
4 March 2019 in Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms