Infrared Electronic Emission Spectrum of Oxygen

The emission spectrum of the positive column of an electric discharge in flowing oxygen has been investigated in the near ir, from 1-micro to 5-micro wavelength. Spectra over a range of pressures from 0.5 Torr to 10 Torr are displayed, and thirteen previously unreported lines of OI measured and assigned. The stronger ir lines are discussed as probable auroral emission features, and the levels 5g(3,5)G(0) of OI are established. Infrared active molecular impurity species present in the oxygen discharge indicate a vibrational temperature in excess of 2000 K, as is also the case for nitrogen discharges under similar conditions. Unlike the nitrogen discharge, that of the oxygen emits an ir spectrum consisting only of atomic lines and is, furthermore, notably deficient in visible emission.