Continuum in the atomic optical model

Abstract
The optical potential in principle gives a complete description of the effect of the target continuum on an electron-scattering problem truncated to a discrete set of channels. A momentum-space form for the optical potential has been derived and computed for the continuum in various approximations for the case of hydrogen. The total ionization cross section is excellently reproduced in the weak-coupling approximation above 100 eV by the most detailed model, and is tolerable as low as 50 eV.