کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
5428358 | 1508670 | 2014 | 7 صفحه PDF | دانلود رایگان |
- Analysis of speed dependence of relaxation rates for CH3Cl-CO2 lines.
- Determination of the model parameters for a semi-empirical theoretical approach.
- Extensive calculations of line widths for large ranges of rotational quantum numbers.
Rotational transitions in CH335Cl mixed with CO2 are recorded at 296Â K and total pressures up to 0.6Â Torr in the frequency interval 186-901Â GHz (1.6-0.3Â mm) for J=6â7, 10â11, 17â18, 22â23, 31â32, 33â34 and K=0-6, using the frequency-modulation spectrometer of the Laboratory PhLAM (Lille, France). These line-shapes are analyzed with the commonly used Voigt profile as well as with more refined Speed-Dependent Voigt and Galatry models accounting for the line narrowing induced, respectively, by the speed-dependence of the relaxation parameters and by velocity-changing collisions. Due to the high line intensities, the fitting procedure involves the full implementation of the Beer-Lambert law instead of its traditional linear approximation. The experimentally deduced J- and K-dependences of the pressure-broadening coefficients are further used to obtain the model parameters of a semi-empirical approach allowing massive calculations of line-shape parameters for enlarged ranges of rotational quantum numbers requested by spectroscopic databases.
Journal: Journal of Quantitative Spectroscopy and Radiative Transfer - Volume 145, September 2014, Pages 50-56