Extended coupled-channels calculations for electron-hydrogen scattering

Abstract

Electron-hydrogen scattering to the 1s, 2s, and 2p states is calculated at 54.42 and 200 eV, and compared with experimental data. Higher-energy reaction channels, including the continuum, are taken into account in two different ways: first, in approximate polarization potentials involving explicit integration over the appropriate kinematic degrees of freedom; second, in a set of seven pseudostates for which the 10-channel pseudoproblem is solved in full. In anticipation of larger and better pseudostate sets, approximations to the pseudoproblem are investigated. They involve second-order treatment of coupling to the pseudostates.