Correction of the influence of the substrate upon the measurement of K-shell ionization cross sections

The K-shell ionization cross sections of Ni and Cr by electron impact have been measured. In the measurements thin targets with a thick substrate were used. The influence of the reflected electrons from the substrate on the measurements has been corrected by means of a detailed calculation of electron transport. By comparison it is shown that the corrected measurement data of K-shell ionization cross section by electron impact are in good agreement with existing experimental data.