Metastable ²Datomic nitrogen in the mid-latitude nocturnal ionosphere

摘要: At night at mid-latitudes the sources of N(²D) in F region are reduced to dissociative recombination NO+. The only important sinks quenching by atomic oxygen and electrons. As a result, photochemical study made nighttime is greatly simplified comparison with one daytime. night, however, optical emission 5200 A resulting from transition N(4S) difficult measure because low intensities. By combining ground-based measurements I coincident satellite observations neutral ion densities temperatures shape profile, we able relate rate efficiency production Assuming 1.0 × 10−9 (Te/300)0.5 cm³ s−1 for electrons, obtain 1.5–2.5 10−12 an (0.8–1.0) ± 30% recent laboratory determination coefficient NO+ 4.3 10−7(Te/300)−0.37 found be good agreement measured densities.