Cross sections for electron capture and loss by H+ and H impact on O and O2

Projectile-charge-changing cross sections for electron capture by H+ and H collisions with O atoms and electron loss by H collisions with O atoms have been determined. The H+ and H energies ranged from 2.0 down to 0.125 keV. The cross-beam technique involved measuring the cross-section ratios for reactions with O-atom targets to those for O2 targets. The O-atom-target cross sections were then obtained by normalizing these ratios to previously measured O2-target cross sections. The experimental apparatus employed is described, and the measured results are compared with other available data.