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Water absorption lines, 931-961 nm - Selected intensities, N2-collision-broadening coefficients, self-broadening coefficients, and pressure shifts in airIntensities were measured for 97 lines of H2O vapor between 932 and 961 nm. The lines were selected for their potential usefulness for remote laser measurements of H2O vapor in the earth's atmosphere. The spectra were obtained with several different H2O vapor abundances and N2 broadening gas pressures; the spectral resolution was 0.046/cm FWHM. Measured H2O line intensities range from 7 x 10 to the -25th to 7 x 10 to the -22nd/cm per (molecules/sq cm). H2O self-broadening coefficients were measured for 13 of these strongest lines; the mean value was 0.5/cm per atm. N2-collision-broadening coefficients were measured for 73 lines, and the average was 0.11 cm per atm HWHM. Pressure shifts in air were determined for a sample of six lines between 948 and 950 nm; these lines shift to lower frequency by an amount comparable to 0.1 of the collision-broadened widths measured in air or N2. The measured intensities of many lines of 300-000 band are much larger than expected from prior computations, in some cases by over an order of magnitude. Coriolis interactions with the stronger 201-000 band appear to be the primary cause of the enhancement of these line intensities.
Document ID
19820045588
Document Type
Reprint (Version printed in journal)
Authors
Giver, L. P. (NASA Ames Research Center Moffett Field, CA, United States)
Gentry, B. (NASA Ames Research Center Moffett Field, CA, United States)
Schwemmer, G. (NASA Goddard Space Flight Center Greenbelt; Maryland, University, College Park, MD, United States)
Wilkerson, T. D. (NASA Ames Research Center Moffett Field, CA, United States)
Date Acquired
August 10, 2013
Publication Date
April 1, 1982
Publication Information
Publication: Journal of Quantitative Spectroscopy and Radiative Transfer
Volume: 27
Subject Category
GEOPHYSICS
Funding Number(s)
CONTRACT_GRANT: NSG-2216
CONTRACT_GRANT: NCA2-OR-420-701
CONTRACT_GRANT: N00014-78-C-0368-00002
Distribution Limits
Public
Copyright
Other