I.R. Radiation of the upper atmosphere

A theory of the i.r. radiation (2–20 μ) of the upper atmosphere (90–250 km height) has been developed. It includes the calculation of concentrations and temperatures as well as the analysis of atomic and molecular level population kinetics. Various excitation and quenching processes are analysed. Results are given for the following bands: NO (5.3μ), NO⁺(4.3μ.), CO (4.7 μ), N¹⁴N¹⁵ (4.4 μ), CO₂(4.3 and 15 μ), H₂O(2.7 and 6.3 μ), N₂O(4.5; 7.8 and 17μ), O₃(9.6 and 14.4 μ). The energy aspect of the problem is discussed. It is found that at a height of 120 km intensity in the region of 2 to 20 μ 3 to 10 is that of the 63 μ line of atomic oxygen. The comparison of theory with the experiment was carried out and satisfactory agreement obtained. The correlations of intensities in i.r. bands and emissions in visible and u.v. spectra were considered.