HIGH ENERGY ELECTRON IMPACT SPECTROSCOPY

Author Institution: Department of Chemistry, Indiana UniversityThe use of high energy (1-40 keV) electron impact spectra to study ionization phenomena will be discussed. Measurements of the angular and energy loss dependence of both scattered and ejected electrons involved with electron impact ionization of atomic helium will be presented. The results are compared with the predictions of the Binary encounter theory and the range of validity of the theory is determined. The large angle $(5^{\circ} - 60^{\circ})$ energy loss spectrum at high incident energies (20--40 keV) is studied to determine the feasibility of using electron scattering to determine Compton profiles. Lower energy (500 eV - 2 keV) studies are carried out over an angular range of $30^{\circ} - 140^{\circ} $ to determine the energy loss spectrum of ejected electrons