Spectral coincidences between emission lines of the CO laser and absorption lines of nitrogen oxides

Several spectral coincidences between carbon-monoxide laser emission lines and absorption lines of NO and N2O4have been observed, and absorption measurements have been taken. These data are presented and discussed along with similar spectral coincidence observations made previously using the helium-neon and iodine lasers. Other coincidences between CO-laser lines and NO2absorption lines are predicted from a study of recently available high-resolution-spectroscopy literature. Due to the narrow line widths of gas-laser lines, the coincidences reported here can be applied to the selective sensing of these constituents in the atmosphere.