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An opacity-sampled treatment of water vaporAlthough the bands of H2O are strong in the spectra of cool stars and calculations have repeatedly demonstrated their significance as opacity sources, only approximate opacities are currently available, due both to the difficulty of accounting for the millions of lines involved and to the inadequacy of laboratory and theoretical data. To overcome these obstacles, a new treatment is presented, based upon a statistical representation of the water vapor spectrum derived from available laboratory data. This statistical spectrum of water vapor employs an exponential distribution of line strengths and random positions of lines whose overall properties are forced to reproduce the mean opacities observed in the laboratory. The resultant data set is then treated by the opacity-sampling method exactly as are all other lines, both molecular and atomic. Significant differences are found between the results of this improved treatment and the results obtained with previous treatments of water-vapor opacity.
Document ID
19900025108
Document Type
Reprint (Version printed in journal)
External Source(s)
Authors
Alexander, David R.
(Wichita State University KS, United States)
Augason, Gordon C.
(NASA Ames Research Center Moffett Field, CA, United States)
Johnson, Hollis R.
(Indiana University Bloomington, United States)
Date Acquired
August 14, 2013
Publication Date
October 15, 1989
Publication Information
Publication: Astrophysical Journal, Part 1
Volume: 345
ISSN: 0004-637X
Subject Category
Atomic And Molecular Physics
Funding Number(s)
CONTRACT_GRANT: NSF AST-82-05800
CONTRACT_GRANT: NCA2-IR-335-402
CONTRACT_GRANT: NSF AST-85-20539
Distribution Limits
Public
Copyright
Other
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