15min:

V. MALATHY DEVI, D. CHRIS BENNER, The College of William and Mary, Williamsburg, VA 23187; MARY ANN H. SMITH, Science Directorate, NASA Langley Research Center, Hampton, VA 23681; ARLAN W. MANTZ, Dept. of Physics, Astronomy and Geophysics, Connecticut College, New London, CT 06320; KEEYOON SUNG AND LINDA R. BROWN, Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Dr.,Pasadena, CA 91109.

High resolution (0.005 cm^-1) absorption spectra of CO and two of its isotopologues (¹³CO and C¹⁸O) were recorded between 3550 and 5250 cm^-1 using the Bruker IFS-125HR Fourier transform spectrometer (FTS) located at the Jet Propulsion Laboratory (JPL) and a specially designed and built coolable 20.38 cm long absorption cell placed within the sample compartment of the FTS. More than 50 spectra of both pure and air-broadened samples of CO, ¹³CO and C¹⁸O were recorded at various temperatures from 150 K to 298 K, with maximum total pressures up to 700 Torr. A multispectrum nonlinear least squares spectrum fitting technique was used to determine the spectral line shape parameters including speed dependence, Lorentz halfwidth coefficients, pressure-induced shift coefficients, and off-diagonal relaxation matrix element coefficients for line mixing. These line shape parameters were obtained for both self- and air-broadening, and temperature dependences of these parameters were determined where possible. As previously done in studies of CO₂, rather than retrieving individual line positions and intensities, we constrained them to their theoretical relationships, including Herman-Wallis terms, determining only the band intensities and rovibrational constants. The results are discussed and compared with values reported in the literature.