Line broadening in the fundamental band of CO in CO-He and CO-Ar mixtures

We present accurate broadening coefficients for many lines of the fundamental band of CO highly diluted in He and Ar at 301.5 K. It is shown that a soft collision model gives a reasonable fit to the data at pressures up to 1 atm. A distinction is drawn between the accuracy with which fitting parameters may be determined and the accuracy with which a spectral profile fits experimental data. Differences between a model profile and the experimental profile are quantified, and the underlying physics omitted from the spectral model is briefly discussed. (C) 1998 Academic Press.