Infrared Radiation from H2O, CO2 or NH3 Collisionally Excited by N2, O or Argon
Final rept. Apr 1972-Jan 1974
CALSPAN CORP BUFFALO NY
Pagination or Media Count:
The experiment described was designed to elicit the infrared radiative properties of molecules of H2O, CO2 or NH3 that have been involved in a single high-energy collision with N2, O, or Argon. A pressure-driven reflected-shock tunnel was used to produce N2, O, and Ar at sufficiently low density that the effect of single collisions could be observed. Excited states are generated at one streamwise location and the associated radiation intensity viewed by an infrared detector at a location farther downstream. The experimental apparatus and diagnostic techniques used to obtain these results are described. The data reduction procedure is discussed which was used to convert the detector output to the appropriate values of the ratio of cross section for collisional excitation to the lifetime of the participating excited state and the excitation cross section. Experimental data for the interaction of N2 -H2O, N2 -CO2, N2-NH3, O-H2O, and Ar-H2O are presented. The appendix provides some semi-empirical formulae which permit correlation of vibrational relaxation data and collisional excitation cross sections.
- Atomic and Molecular Physics and Spectroscopy