NASA Logo

NTRS

NTRS - NASA Technical Reports Server

Back to Results
Air- and Self-Broadened Half Widths, Pressure-Induced Shifts, and Line Mixing in the Nu(sub 2) Band of (12)CH4Lorentz self- and air-broadened half width and pressure-induced shift coefficients and their dependences on temperature have been measured from laboratory absorption spectra for nearly 130 transitions in the nu(sub 2) band of (12)CH4. In addition line mixing coefficients (using the relaxation matrix element formalism) for both self- and airbroadening were experimentally determined for the first time for a small number of transitions in this band. Accurate line positions and absolute line intensities were also determined. These parameters were obtained by analyzing high-resolution (approx. 0.003 to 0.01 per cm) laboratory spectra of high-purity natural CH4 and air-broadened CH4 recorded at temperatures between 226 and 297 K using the McMath-Pierce Fourier transform spectrometer (FTS) located at the National Solar Observatory on Kitt Peak, Arizona. A multispectrum nonlinear least squares technique was used to fit short (5-15 per cm) spectral intervals in 24-29 spectra simultaneously. Parameters were determined for nu(sub 2) transitions up to J" = 16. The variations of the measured broadening and shift parameters with the rotational quantum number index and tetrahedral symmetry species are examined. The present results are also compared with previous measurements available in the literature.
Document ID
20150001213
Acquisition Source
Langley Research Center
Document Type
Reprint (Version printed in journal)
Authors
Smith, M. A. H.
(NASA Langley Research Center Hampton, VA, United States)
Benner, D. Chris
(College of William and Mary Williamsburg, VA, United States)
Pedroi-Cross, A.
(Lethbridge Univ. Lethbridge, Alberta, Canada)
Devi, V. Malathy
(College of William and Mary Williamsburg, VA, United States)
Date Acquired
February 3, 2015
Publication Date
August 14, 2013
Publication Information
Publication: Journal of Quantitative Spectroscopy & Radiative Transfer
Volume: 133
Subject Category
Instrumentation And Photography
Inorganic, Organic And Physical Chemistry
Report/Patent Number
NF1676L-16790
Funding Number(s)
WBS: WBS 281945.02.42.01.98
Distribution Limits
Public
Copyright
Other

Available Downloads

There are no available downloads for this record.
No Preview Available