Charged-particle production in low-energy H+H2 and H+He collisions

Absolute cross sections for producing H+, H-, H+2, He+, and e- have been measured for fast hydrogen atom impact on H2 and He targets. The hydrogen atom energy ranged between 50 eV and 3.0 keV. For the H+H2 reaction, the dominant ion-formation process for hydrogen atom energies below 250 eV was found to be H-+H+2 production. For He targets, production of H+ dominated over the entire hydrogen atom energy range. The results are compared, where possible, with the data of other investigators and are discussed in terms of possible reaction mechanisms