Dissociative and non-dissociative ionization of the O2 molecule by He+ impact

Abstract

Absolute cross sections for the dissociative and non-dissociative ionization of the O2 molecule, accompanied or not by the projectile electron loss, have been measured in coincidence with the final projectile charge states for the impact of 0.75–3.5 MeV He+ ions. The fragmentation patterns are analyzed in comparison with data for photon, electron and heavy-ion impact available in the literature for different collision channels. This analysis shows that the fragmentation pathways depend not only on the projectile energy and charge state, but also on the particular collision channel involved. It is also shown that the fragmentation fractions follow the same scaling rule obtained previously for the N2 molecule by Melo et al (2006 J. Phys. B: At. Mol. Opt. Phys. 39 3519).