Spectral Line Parameters for the ν9Band of Ethane

Ethane is a prominent contributor to the spectrum of Titan, particularly in the region of the v(9) band at 12 mu m. A multispectrum nonlinear least squares fitting program was applied to laboratory spectra of ethane to measure accurate positions, absolute intensities, N-2- and self-broadened half-width coefficients and their temperature dependences for a large number transitions. These measurements include several (p)Q and (r)Q sub-bands (and other sub-bands such as P-p, R-r) in the v(9) fundamental band of (C2H6)-C-12 centered near 822 cm(-1). Positions and intensities were measured for 3771 transitions. N-2- and self-broadened half-width coefficients were determined for over 1700 transitions while temperature dependence exponents were retrieved for over 1350 of those transitions. Of these, many measurements (mostly line positions and intensities) belong to the (C2H6)-C-12 v(9)+v(4)-v(4) and the v(9)+2v(4)-2v(4) hot bands, (CCH6)-C-13-C-12 v(9) band and unidentified transitions. Forty-three high resolution (0.0016-0.005 cm(-1)) infrared laboratory absorption spectra recorded at temperatures between similar to 150 and 298 K were fitted simultaneously to retrieve these parameters.