Internal consistency of the coupled-channels optical calculation for e-H scattering

Abstract
The coupled-channels optical (CCO) calculation of electron-atom scattering involves the solution of a set of coupled integral equations for a finite set of channels, with the effect of the remaining channels included by the optical potential. For discrete channels the calculation of the optical potential can be verified within the framework of the coupled-channels (CC) calculations: 54.4 eV electron scattering on hydrogen is calculated in a three-channel model with the n=2 channels either explicitly coupled or treated by different approximations to the optical potential. The same is done for the n=3 channels in a six-channel model. In both cases the authors find that the CCO model reproduces the corresponding CC calculation to a sufficient accuracy, which verifies internal consistency of their approach. They present the results of the 6CCO calculation at 54.4 eV and find them not to be significantly different from the 3CCO results recently reported by Bray et al. (1990), as expected.