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Updated: Jul 15, 2026

Characterizing Far-infrared Laser Emissions and the Measurement of Their Frequencies
Published on: December 18, 2015
Measurements of collisional broadening coefficients by infrared polarization spectroscopy
Z T Alwahabi1, J Zetterberg, Z S Li
1School of Chemical Engineering, University of Adelaide, SA, 5005, Australia. zalwahab@chemeng.adelaide.edu.au
Abstract:
We present measurements of collisional broadening coefficients, obtained at atmospheric pressure, by polarization spectroscopy. Using tunable single mode laser radiation at approximately 2 microm, high-resolution infrared polarization spectra were recorded for CO2-Ar and CO2-He binary mixtures. The recorded polarization spectra were fitted with a Lorentzian cubed function form to obtain the broadening coefficients. The full-width at half-maxima (FWHM) collisional broadening rates of CO2 by Ar and He, for the R14 (12 degrees1<--00 degrees0) line, have been determined to be 0.161+/-0.018 cm-1 atm-1 and 0.1823+/-0.0032 cm-1 atm-1, respectively.
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