Electron loss by helium atoms passing through inert gases and molecular hydrogen, nitrogen, and oxygen

The Born approximation and free-scattering model have been used to calculate the electron-loss cross section from atomic helium incident on He, Ne, Ar, and Kr atoms and on H2, N2, and O2 molecules. For the molecules the phase difference between the scattered wave emanating from the two atoms has been considered in the separated-atom approximation. The vibrational damping of the molecule is also taken into account. It is shown that the effect of phase is very small