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 N
2
O
4
have 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 NO
2
absorption 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.