Cross-sections for electron impact ionization of O₂

Using a crossed electron beam—molecular beam collision geometry and the relative flow technique measurements have been made to generate a uniform set of electron impact ionization cross-section data for O₂ for electron impact energies from threshold to 1000 eV. Present values of total, partial and dissociative ionization cross-sections are compared with previously published data. Cross-sections for the formation of O²⁺ from O₂ have been measured for the first time