Elastic Scattering of Low-Energy Electrons from Metastable Helium

Abstract

The cross section for the elastic scattering of electrons in the energy range 0.003 to 10.0 eV by metastable helium atoms in the $2{}_{}{}^3{}_{}{}^{}S$ state has been computed using various forms of the polarized-orbital method. A low-energy spin-flip cross section is also obtained. The perturbed atomic wavefunctions required in the polarized-orbital method were obtained by solving the coupled equations of Hartree-Fock perturbation theory. It is shown that the adiabatic polarization potential produces an effective interaction which is too strongly attractive, where-as if the polarization effect is compensated by the distortion potential of nonadiabatic origin, the interaction is too repulsive.