The effect of target atom polarization and wavefunction distortion in (e - 2e) ionization of hydrogen

Abstract
Calculations using the distorted-wave first Born model are reported for the triple differential cross section for electron-impact ionization of atomic hydrogen at low energy. They are carried out in the coplanar asymmetric geometry for various deflection angles. Different kinematics are considered: unequal energy sharing between the outgoing electrons at 54.4 eV and equal energy sharing at 27.2, 17.6 and 15.6 eV. We attempt to improve the theoretical description of the initial state and propose four models, three of which include a polarization of the target orbital. The associated polarization potential is used in addition to the static and the static-exchange potentials to calculate the distorted wave. We account for electron-pair correlation in the final state by use of a Gamow correction factor.