ELECTRON-SCATTERING BY ATOMIC-HYDROGEN - ELASTIC AND INELASTIC PHENOMENA AT 13.9-200 EV

A six-state coupled-channel optical potential method for electron-atom scattering is applied to electron-hydrogen scattering at energies of 13.87, 16.46, 19.58, 35, 40, 54.4, 100, and 200 eV. The n = 1, 2, and 3 channels are coupled explicitly, whereas the rest of the excited states of the atom including the continuum are taken into account via the ab initio complex nonlocal polarization potential. The differential and integrated cross sections, as well as the exchange asymmetries for n = 1 and 2 channels, the total cross section, and the lambda, R, and I parameters for the 2p excitation, are presented at each energy. The ratio of differential cross sections for n = 1 to 2, and for 2s to 2p, and the 2s + 2p differential cross sections are found to be in good agreement with experiment. There are still some discrepancies between experiment and theory for the 2p angular correlation parameters lambda, R, and I.