Experimental investigation of CO vibrational deactivation in a supersonic cooling gas flow

The vibrational relaxation time of CO molecules at collisions with H atoms was measured in shock tube experiments by means of the CARS-spectroscopy me thod. The measurements of the CO vibrational temperature at gas temperature s of 1800-3000 K were performed in a supersonic cooling gas flow. The gas w as heated behind the incident and reflected shock wave and then flowed out of a wedge-shaped nozzle. H atoms were generated in the reflected shock wav e because of dissociation of H-2 and H2O admixtures. The extremely high eff iciency of H atoms in CO vibrational deactivation was confirmed.