Width and Shift Coefficients in O2-Broadened CO2: Bands at 6227 and 6348 cm-1 Using a Constrained Multispectrum Analysis.

Lorentz half width and pressure-induced shift coefficients, and speed dependence parameters for oxygen-broadened CO2 transitions in the 30013←00001 (6227 cm-1) and 30012←00001 (6348 cm-1) bands were measured employing a non linear least squares multispectrum fitting technique. The high-resolution spectra used in the analysis were recorded using the McMath-Pierce Fourier transform spectrometer (FTS) located at the National Solar Observatory (NSO) on Kitt Peak, Arizona. The spectra were obtained at room temperature using the long path, 6 m base path White cell available at NSO. The multispectrum fitting algorithm employing Voigt line profiles was modified to include line mixing and speed dependence and was used to fit simultaneously a total of 19 spectra in the 6120-6280 cm-1 and 6280-6395 cm-1 spectral regions. The results from the present study have been compared with measurements available in the literature. Combining the O2-broadening measurements from present work with the previously determined air-broadening results, N2-broadened width and shift coefficients are calculated and compared with other reported values. [ABSTRACT FROM AUTHOR]