Electron impact excitation of H and He+. IV. Orientation and alignment of the 2p state

Abstract
For pt.III see ibid., vol.8, no.7, p.1053 (1975). Orientation and alignment effects observable in coincidence measurements of Ly alpha photons and scattered electrons are discussed. Results, in the DWPO II model are presented for the Fano-Macek parameters. Computer generated maps of the coincidence rate as a function of scattering electron angle and photon emission angle are presented at two energies, and show interesting, energy-dependent, symmetries.