Elastic Electron-Atom Scattering at Intermediate Energies

We analyze elastic electron-atom scattering at intermediate and high energies by combining the Born series and eikonal series to get a consistent picture of the scattering amplitude through order ${k_i}^{-2\mathrm{}}$. Our eikonal-Born-series approach is compared with the usual Glauber approximation, which is shown to be seriously deficient. We also discuss the Schwinger variational principle, exchange effects, and forward dispersion relations. Applications are made to the elastic scattering of electrons by atomic hydrogen and helium. The agreement between our results and the experimental data is very good.