Application of the Impulse Approximation to the Scattering of Electrons by Atoms. I. Inelastic Scattering by Hydrogen Atoms

A calculation of the ionization cross section and the excitation cross section to the $2S$ and $2P$ states of hydrogen atoms by collision with electrons is carried through by the use of an impulse approximation. The results are then compared to the experimental data and to various other theoretical calculations. The cross sections obtained compare favorably with experiment. The calculations carried out by these methods are no more complicated than the usual approximation methods and are easily adaptable for use with more complicated atoms.