Dissociative ionization of H2 and D2 by electron impact near threshold

We have studied the dissciative ionization of H2 and D2 by electron impact. It is found that in the vicinity of the 2Σ+g dissociation threshold of H+2 (18.08 eV) a significant fraction of the produced protons originates from the process e + H2 → H− + H+ + e (threshold at 17.34 eV). Similar results are found for D2

Angular distribution of electrons ejected by charged particles. IV. Combined classical and quantum-mechanical treatment

Angular distributions of electrons ejected from helium by 100 and 300 keV protons have been calculated by a method which is a comination of the classical three-body collision theory and the quantum-mechanical Born approximation. The results of this theory have been compared with the corresponding experimental data and results of the Born and the classical three-body collision theories. The results of the combined method are in close agreement with the experimental data over the whole range of the ejection angles

H2− formation in electron impact ionization of H2 near threshold

New features in near threshold ionization spectra of H2 which can be correlated with two series of H2− states proceeding across the H2+ threshold, indicate a need for coincidence experiments that differentiate between one and two electron decay modes of H2−