The dissociative recombination of O2+ in the ionosphere

Aeronomical determinations of the dissociative recombination reaction rate coefficient for O₂⁺, α, depend directly on a knowledge of the rate coefficient for the charge exchange of O⁺ with O₂, k. A re-evaluation of the aeronomical determination of α using Atmosphere Explorer satellite data is necessary in the light of a subsequent laboratory measurement of k. The results reported here are in reasonable agreement with laboratory determinations to within the uncertainty of the analysis for night-time conditions. However, for data obtained under sunlit conditions the aeronomical determination differs significantly from the laboratory measurements. The results imply that the state of the O₂⁺ molecule resulting from the major thermospheric processes requires further examination.