Atomic line radiation in the infrared

The present paper considers atomic infrared line emission from states of high angular momentum, which should be significally populated in a high-temperature, equilibrium (LTE) gas. Such states are shown to give rise to a “universal” series of strong lines, the first member of which is at ～4μ, and corresponds to the puzzling 4 μ-feature by Taylor and Caledonia.Several of the higher members of the predicated series are found in cesium spectra taken in our laboratory.