Nitric oxide delta band emission in the Earth's atmosphere: Comparison of a measurement and a theory

The altitude dependent emission rate in the δ‐bands of nitric oxide has been measured in the earth's atmosphere at night by a scanning ultraviolet spectrometer. The reaction responsible is the two‐body association of nitrogen and oxygen atoms. The measurements reveal a vertical intensity beneath the layer for the δ‐band system of 19 R. The horizontal emission rate increases from 70 R at 117 km to 140 R at 150 km. The data have been analyzed with a one‐dimensional, time‐dependent, vertical‐transport model of odd nitrogen photochemistry. The calculated and measured intensities agree if the quenching of N(²D) by atomic oxygen is near 5 × 10−13 cm³ s−1. The diurnal variation of δ‐band emission, N(4S), and NO densities resulting from model calculations are presented and discussed.