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Applied Optics

Applied Optics

APPLICATIONS-CENTERED RESEARCH IN OPTICS

  • Vol. 22, Iss. 23 — Dec. 1, 1983
  • pp: 3701–3710

Water-vapor continuum CO2 laser absorption spectra between 27°C and −10°C

Gary L. Loper, Maureen A. O'Neill, and Jerry A. Gelbwachs  »View Author Affiliations


Applied Optics, Vol. 22, Issue 23, pp. 3701-3710 (1983)
http://dx.doi.org/10.1364/AO.22.003701


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Abstract

Water continuum CO2 laser absorption spectra are reported for temperatures between 27 and −10°C. The continuum is found to possess a negative temperature coefficient. The results obtained suggest that the magnitude of this temperature coefficient increases with increasing water pressure and decreasing temperature. The temperature coefficients between 27 and 10°C for air mixtures containing 3.0- and 7.5-Torr water vapor are −2.0 ± 0.4 and −2.9 ± 0.5%/°C, respectively. For mixtures with 3.0-Torr water the 10–0°C temperature coefficient is −7.7 ± 0.2%/°C. The temperature and water pressure dependencies observed for the continuum suggest that while both collisional broadening and water dimer mechanisms contribute to the continuum, the dimer mechanism is more important over this temperature range.

© 1983 Optical Society of America

History
Original Manuscript: July 25, 1983
Published: December 1, 1983

Citation
Gary L. Loper, Maureen A. O'Neill, and Jerry A. Gelbwachs, "Water-vapor continuum CO2 laser absorption spectra between 27°C and −10°C," Appl. Opt. 22, 3701-3710 (1983)
http://www.opticsinfobase.org/ao/abstract.cfm?URI=ao-22-23-3701


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References

  1. K. M. Haught, J. A. Dowling, Opt. Lett. 1, 121 (1977). [CrossRef] [PubMed]
  2. R. E. Roberts, J. E. A. Selby, L. M. Biberman, Appl. Opt. 15, 2085 (1976). [CrossRef] [PubMed]
  3. K. O. White, W. R. Watkins, C. W. Bruce, R. E. Meredith, F. G. Smith, Appl. Opt. 17, 2711 (1978). [CrossRef] [PubMed]
  4. J. H. McCoy, D. B. Rensch, R. K. Long, Appl. Opt. 8, 1471 (1969). [CrossRef] [PubMed]
  5. D. E. Burch, “Investigation of the Absorption of Infrared Radiation by Atmospheric Gases,” Semi-Annual Technical Report, contract F19628-69-C-0263, Aeronutronic Report U-4784 (Jan.1970).
  6. K. J. Bignell, Q. J. R. Meteorol. Soc. 96, 390 (1970). [CrossRef]
  7. V. N. Arefev, V. I. Dianov-Klokov, V. F. Radionov, N. I. Sizov, Opt. Spectrosc. 39, 560 (1975);V. N. Arefev, V. I. Dianov-Klokov, Opt. Spectrosc. 42, 488 (1977).
  8. R. J. Nordstrom, M. E. Thomas, J. C. Peterson, E. K. Damon, R. K. Long, Appl. Opt. 17, 2724 (1978). [CrossRef] [PubMed]
  9. D. A. Gryvnak, D. E. Burch, R. L. Alt, D. K. Zgonc, “Infrared Absorption by CH4, H2O, and CO2,” AFGL-TR-76-0246, Final Report, contract F19628-76-C-0067, Aeronutronic Report U-6275 (Dec.1977).
  10. G. P. Montgomery, Appl. Opt. 17, 2299 (1978). [CrossRef] [PubMed]
  11. G. L. Loper, M. A. O'Neill, J. A. Gelbwachs, “Below Room Temperature Water Continuum Absorption Within the 8–12 μm Atmosphere Transmission Window,” Aerospace Corp. Report TR-0083 (8494)-1 (1983).
  12. M. S. Shumate, R. T. Menzies, J. S. Margolis, L.-G. Rosengren, Appl. Opt. 15, 2480 (1976). [CrossRef] [PubMed]
  13. J. C. Peterson, “A Study of Water Vapor Absorption at CO2 Laser Frequencies Using a Differential Spectrophone and White Cell,” Dissertation, Ohio State U., (June1978).
  14. J. C. Peterson, M. E. Thomas, R. J. Nordstrom, E. K. Damon, R. K. Long, Appl. Opt. 18, 834 (1979). [CrossRef] [PubMed]
  15. M. E. Thomas, “Tropospheric Water Vapor Absorption in the Infrared Window Regions,” Dissertation, Ohio State U., (Aug.1979).
  16. R. J. Nordstrom, M. E. Thomas, “The Water Vapor Continuum as Wings of Strong Absorption Lines,” in Atmospheric Water Vapor, A. Deepak, T. D. Wilkerson, L. H. Ruhnke, Eds. (Academic, New York, 1980).
  17. S. A. Clough, F. X. Kneizys, R. Davies, R. Gamache, R. Tipping, “Theoretical Line Shape for H2O Vapor; Application to the Continuum,” in Atmospheric Water Vapor, A. Deepak, T. D. Wilkerson, L. H. Ruhnke, Eds. (Academic, New York, 1980).
  18. S. H. Suck, J. L. Kassner, Y. Yamaguchi, Appl. Opt. 18, 2609 (1979). [CrossRef] [PubMed]
  19. S. H. Suck, A. E. Wetmore, T. S. Chen, J. L. Kassner, Appl. Opt. 21, 1610 (1982). [CrossRef] [PubMed]
  20. H. R. Carlon, Appl. Opt. 17, 3192 (1978);Infrared Phys. 19, 49, 549 (1979);H. R. Carlon, C. S. Harden, Appl. Opt. 19, 1776 (1980). [CrossRef] [PubMed]
  21. T. F. Deaton, D. A. Depatie, T. W. Walker, Appl. Phys. Lett. 26, 300 (1975). [CrossRef]
  22. G. L. Loper, A. R. Calloway, M. A. Stamps, J. A. Gelbwachs, Appl. Opt. 19, 2726 (1980). [CrossRef] [PubMed]
  23. J. S. Ryan, M. H. Hubert, R. A. Crane, Appl. Opt. 22, 711 (1983). [CrossRef] [PubMed]
  24. R. A. McClatchey, W. S. Benedict, S. A. Clough, D. E. Burch, R. F. Calfee, K. Fox, L. S. Rothman, J. S. Garing, AFCRL Atmospheric Absorption Line Parameters Compilation, AFCRL-TR-73-0096, Bedford, Mass. (1973).
  25. A pure linear dependence is observed only when the absorption strength of the local water line is significantly greater than the absorption strength of the underlying water continuum.
  26. D. E. Burch, D. A. Gryvnak, G. H. Piper, “Infrared Absorption by H2O and N2O,” contract F19628-73-C-0011, Aeronutronic Report U-6026 (July1973);D. E. Burch, D. A. Gryvnak, F. J. Gates, “Continuum Absorption by H2O Between 300 and 825 cm−1,” AFCRL-TR-74-0377, Aeronutronic Report U-6095 (Sept.1974).
  27. The so-called self-broadening coefficient Cs(λ,T) plotted vs temperature in Fig. 8 is most often defined in the literature through the relationabs(λ,T)=Cs(λ,T)wH2O[pH2O+γ(λ,T)(P−pH2O)].Here abs(λ,T) is the water continuum absorption coefficient at a particular wavelength and temperature, wH2O is the density of water vapor in units of molecules/cm3, pH2O is the water partial pressure, P is the total pressure in units of atmospheres, and γ(λ,T) = Cf(λ,T)/Cs(λ,T) is the foreign-broadening to self-broadening coefficient ratio.
  28. The water dimer model of Suck and co-workers18,19 predicts that the water continuum absorption strength varies with temperature by the factorT−3∏i=16{exp(−hυi/2kT)/[1−exp(−hυi/kT)]}exp(−ΔH°/RT),where h is Planck's constant, k is Boltzmann's constant, and the υi correspond to the frequencies of the six intermolecular vibrational modes of the water dimer. Here ΔH° is the water vapor dimer electronic binding energy at 0 K, while R is the gas law constant, and T is the temperature in kelvins. On the basis of molecular orbital calculations, Suck and co-workers19 chose the binding energy to be −6.5 kcal/mole. The dimer intermolecular frequencies predicted by Owicki et al.29 (593, 496, 189, 168, 161, and 98 cm−1) have been assumed by Suck et al.
  29. J. C. Owicki, L. L. Shipman, H. A. Scheraga, J. Phys. Chem. 79, 1794 (1975). [CrossRef]
  30. The self-broadening coefficient Cs(λ,T) and foreign-broadening coefficient Cf(λ,T) defined in Ref. 27 can be calculated from the linear and quadratic coefficients a(λ,T) and b(λ,T) in Table II through the relationshipsCf(λ,T)=a(λ,T)P(pH2OwH2O),Cs(λ,T)=pH2OwH2O[b(λ,T)+a(λ,T)/P].The Cs values shown at 27, 10, 0, and −10°C in Fig. 8 were calculated from averages of Cs (λ,T) data determined within the laser 10.4-μm band P-branch, where local water absorption line contributions are negligible.
  31. For most atmospheric conditions, the magnitude of the continuum absorption is primarily governed by its water pressure quadratic component. From the linear and quadratic coefficients in Table II, it is observed that the quadratic water pressure component contributes predominantly to the total water absorption coefficient at 27 and 10°C for water pressures greater than ∼3 and 2 Torr, respectively. For lower temperatures, the quadratic component would be the major contributor to the continuum at even lower pressures.
  32. R. R. Patty, G. M. Russwurm, W. A. McClenny, D. R. Morgan, Appl. Opt. 13, 2850 (1974). [CrossRef] [PubMed]
  33. A. Mayer, J. Comera, H. Charpentier, C. Jaussaud, Appl. Opt. 17, 391 (1978). [CrossRef] [PubMed]
  34. U. Persson, B. Marthinsson, J. Johansson, S. T. Eng, Appl. Opt. 19, 1711 (1980). [CrossRef] [PubMed]
  35. E. H. Christy, K. H. Faller, in Second Joint Conference on Sensing of Environmental Pollutants, 10– 12 Dec. 1973, Washington, D.C., paper 23.
  36. R. J. Brewer, C. W. Bruce, J. L. Mater, Appl. Opt. 21, 4092 (1982). [CrossRef] [PubMed]

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