The 1s-2s and 1s-2p excitation of atomic hydrogen by electron impact

The 1s to 2s and 1s to 2p total and differential cross sections for electron impact excitation of atomic hydrogen are calculated from 13 eV to 300 eV. The 1s-2s-2p close-coupling approximation is used for the low partial waves and the unitarized Born approximation for the high partial waves. At the highest energy up to 500 partial waves are included. The calculated differential cross sections are in quite good agreement with the measurements of Williams and Willis (1975).