| Abstract: | The vibrational excitation of HF occurring behind incident shock waves has been studied in the temperature range of 1400°K to 4100°K. The extent of excitation was determined as a function of time by continuously monitoring the emission intensity from the 1–0 band of HF centered at 2.5 μ. The data were interpreted in terms of the process  and gave a value of  for M = HF. The corresponding result for (τp)?1Ar was found to be insignificant in comparison to this result. Data were also obtained for the effect of F atoms upon the relaxation rate, i.e., it was found that  |
