ELECTRON-IMPACT-IONIZATION CROSS-SECTION FOR THE HYDROGEN-ATOM

A distorted-wave Born exchange approximation was used to calculate the cross section for electron-impact ionization of the hydrogen atoms. B oth the integral and energy-differential cross section were calculated . The results were compared with the latest experimental data and othe r theoretical calculations. Comparison shows that the calculations agr ee with differential cross-section measurements in general. For integr al cross sections the calculation shows a better agreement with an ear lier measurement [M.B. Shah, D. S. Elliott, and H. B. Gilbody, J. Phys . B 20, 3501 (1987)] in which the cross sections ate normalized to the first Born approximation.