ELECTRON-IMPACT IONIZATION OF ATOMIC-HYDROGEN AT INTERMEDIATE ENERGIES

The electron-impact ionization of atomic hydrogen at intermediate exce ss energies is considered in the situation where the two continuum ele ctrons escape with substantially different velocities and coplanar wit h the incident direction. Calculations are performed within a model wh ere the three-body final state is described by a product wave function consisting of three symmetrical, Coulomb-type functions. Each of thes e functions describes the motion of a particular two-body subsystem in the presence of the third charged particle. A comprehensive compariso n with available experimental data is presented, and the results are c ontrasted with those of other theoretical models. Generally, good agre ement is found with the absolute measurements; however, in some cases discrepancies between various theoretical predictions and experimental findings are obvious, which highlights the need for a theoretical and experimental benchmark study of these reactions.