Distributions in Energy and Angle of Electrons Ejected from Molecular Hydrogen by 0.3-1.5-MeV Protons

Cross sections for the ejection of electrons, differential in electron energy and angle of emission, have been measured for energetic protons on molecular hydrogen. Electron-energy distributions are presented for ten angles between 20 and 130 deg for each of five proton energies between 0.3 and 1.5 MeV. The results are compared with calculations based on binary-encounter theory, the Born approximation, and the Faddeev equations. Qualitative agreement with the latter provides supporting evidence for the inclusion of a long-range electron-proton interaction in the collision theory for proton energies as high as 1.5 MeV.