Abstract

Air-broadened and N2-broadened halfwidth and pressure shift coefficients of 294 transitions in the ν4 and ν2 bands of 12CH4 have been measured from laboratory absorption spectra recorded at room temperature with the Fourier transform spectrometer in the McMath solar telescope facility of the National Solar Observatory. Total pressures of up to 551 Torr were employed with absorption paths of 5–150 cm, CH4 volume mixing ratios of 2.6% or less, and resolutions of 0.005 and 0.01 cm−1. A nonlinear least-squares spectral fitting technique has been utilized in the analysis of the twenty-five measured spectra. Lines up to J″ = 18 in the ν4 band and J″ = 15 in the ν2 band have been analyzed.

© 1988 Optical Society of America

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    [CrossRef]
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    [CrossRef]
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    [CrossRef]
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    [CrossRef]
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    [CrossRef]
  27. G. Yamamoto, M. Hirono, “Rotational Line Width of Methane,” J. Quant. Spectrosc. Radiat. Transfer 11, 1537 (1971).
    [CrossRef]
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    [CrossRef]
  29. P. Varanasi, “Collision-Broadened Half-Widths and Shapes of Methane Lines,” J. Quant. Spectrosc. Radiat. Transfer 11, 1711 (1971).
    [CrossRef]
  30. D. C. Benner, C. P. Rinsland, V. M. Devi, “Air-Broadened Halfwidths in the ν3 Band of 12CH4,” presented at Forty-first Symposium on Molecular Spectroscopy, 17 June 1986, Columbus, OH (1986), paper TB5.
  31. P. Varanasi, G. D. T. Tejwani, “Experimental and Theoretical Studies on Collision-Broadened Lines in the ν4-Fundamental of Methane,” J. Quant. Spectrosc. Radiat. Transfer 12, 849 (1972).
    [CrossRef]
  32. R. L. Barger, J. L. Hall, “Pressure Shift and Broadening of Methane Line at 3.39 μ Studied by Laser-Saturated Molecular Absorption,” Phys. Rev. Lett. 22, 4 (1969).
    [CrossRef]
  33. J. S. Margolis, “Self-Broadened Half-Widths and Pressure Shifts for the R-Branch J-Manifolds of the 3ν3 Methane Band,” J. Quant. Spectrosc. Radiat. Transfer 11, 69 (1971).
    [CrossRef]
  34. A. S. Pine, “High-Resolution Methane ν3-Band Spectra Using a Stabilized Tunable Difference-Frequency Laser System,” J. Opt. Soc. Am. 66, 97 (1976).
    [CrossRef]
  35. J. H. Shaw, N. Tu, D. L. Agresta, “Sources of Systematic Errors in Line Intensities,” Appl. Opt. 24, 2437 (1985).
    [CrossRef] [PubMed]
  36. J. Ballard, W. B. Johnson, “Self-Broadened Widths and Absolute Strengths of 12CH4 Lines in the 1310–1370-cm−1 Region,” J. Quant. Spectrosc. Radiat. Transfer 36, 365 (1986).
    [CrossRef]

1987

1986

J. Ballard, W. B. Johnson, “Self-Broadened Widths and Absolute Strengths of 12CH4 Lines in the 1310–1370-cm−1 Region,” J. Quant. Spectrosc. Radiat. Transfer 36, 365 (1986).
[CrossRef]

1985

1984

1983

V. M. Devi, B. Fridovich, D. G. S. Snyder, G. D. Jones, P. P. Das, “Tunable Diode Laser Measurements of Intensities and Lorentz Broadening Coefficients of Lines in the ν2 Band of 12CH4,” J. Quant. Spectrosc. Radiat. Transfer 29, 45 (1983).
[CrossRef]

C. P. Rinsland, D. C. Benner, D. J. Richardson, R. A. Toth, “Absolute Intensity Measurements of the (1110)II ← (00°0) Band of 12C16O2 at 5.2 μm,” Appl. Opt. 22, 3805 (1983).
[CrossRef] [PubMed]

V. M. Devi, B. Fridovich, G. D. Jones, D. G. S. Snyder, “Strengths and Lorentz Broadening Coefficients for Spectral Lines in the ν3 and ν2 + ν4 Bands of 12CH4 and 13CH4,” J. Mol. Spectrosc. 97, 333 (1983).
[CrossRef]

P. Varanasi, L. P. Giver, F. P. J. Valero, “Thermal Infrared Lines of Methane Broadened by Nitrogen at Low Temperatures,” J. Quant. Spectrosc. Radiat. Transfer 30, 481 (1983).
[CrossRef]

R. R. Gamache, R. W. Davies, “Theoretical Calculations of N2-Broadened Halfwidths of H2O Using Quantum Fourier Transform Theory,” Appl. Opt. 22, 4013 (1983).
[CrossRef] [PubMed]

1981

A. S. Pine, “Precision Collisional Lineshapes by Difference-Frequency Laser Spectroscopy,” Proc. Soc. Photo-Opt. Instrum. Eng. 277, 64 (1981).

1980

A. S. Pine, “Collisional Narrowing of HF Fundamental Band Spectral Lines by Neon and Argon,” J. Mol. Spectrosc. 82, 435 (1980).
[CrossRef]

1978

R. W. Davies, B. A. Oli, “Theoretical Calculations of H2O Linewidths and Pressure Shifts: Comparison of the Anderson Theory with Quantum Many-Body Theory for N2 and Air-Broadened Lines,” J. Quant. Spectrosc. Radiat. Transfer 20, 95 (1978).
[CrossRef]

A. Chedin, N. Husson, N. A. Scott, D. Gautier, “ν4 Band of Methane (12CH4 and 13CH4). Line Parameters and Evaluation of Jovian Atmospheric Transmission at 7.7 μm,” J. Mol. Spectrosc. 71, 343 (1978).
[CrossRef]

1976

1975

G. D. T. Tejwani, P. Varanasi, K. Fox, “Collision-Broadened Linewidths of Tetrahedral Molecules—II. Computations for CH4 Lines Broadened by N2, O2, He, Ne and Ar,” J. Quant. Spectrosc. Radiat. Transfer 15, 243 (1975).
[CrossRef]

1974

P. Varanasi, “Collision-Broadened Line Widths of Tetrahedral Molecules-I. Theoretical Formulation,” J. Quant. Spectrosc. Radiat. Transfer 14, 995 (1974).
[CrossRef]

G. D. T. Tejwani, K. Fox, “Calculated Linewidths for CH4 Broadened by N2 and O2,” J. Chem. Phys. 60, 2021 (1974).
[CrossRef]

R. S. Eng, P. L. Kelley, A. R. Calawa, T. C. Harman, K. W. Nill, “Tunable Diode Laser Measurements of Water Vapour Absorption Line Parameters,” Mol. Phys. 28, 653 (1974).
[CrossRef]

1973

R. S. Eng, P. L. Kelley, A. Mooradian, A. R. Calawa, T. C. Harman, “Tunable Laser Measurements of Water Vapor Transitions in the Vicinity of 5 μm,” Chem. Phys. Lett. 19, 524 (1973).
[CrossRef]

1972

F. A. Blum, K. W. Nill, P. L. Kelley, A. R. Calawa, T. C. Harman, “Tunable Infrared Laser Spectroscopy of Atmospheric Water Vapor,” Science 177, 694 (1972).
[CrossRef] [PubMed]

R. S. Eng, A. R. Calawa, T. C. Harman, P. L. Kelley, A. Javan, “Collisional Narrowing of Infrared Water-Vapor Transitions,” Appl. Phys. Lett. 21, 303 (1972).
[CrossRef]

P. Varanasi, G. D. T. Tejwani, “Experimental and Theoretical Studies on Collision-Broadened Lines in the ν4-Fundamental of Methane,” J. Quant. Spectrosc. Radiat. Transfer 12, 849 (1972).
[CrossRef]

1971

G. Yamamoto, M. Hirono, “Rotational Line Width of Methane,” J. Quant. Spectrosc. Radiat. Transfer 11, 1537 (1971).
[CrossRef]

G. D. T. Tejwani, P. Varanasi, “Calculation of Collision-Broadened Linewidths in the Infrared Bands of Methane,” J. Chem. Phys. 55, 1075 (1971).
[CrossRef]

P. Varanasi, “Collision-Broadened Half-Widths and Shapes of Methane Lines,” J. Quant. Spectrosc. Radiat. Transfer 11, 1711 (1971).
[CrossRef]

J. S. Margolis, “Self-Broadened Half-Widths and Pressure Shifts for the R-Branch J-Manifolds of the 3ν3 Methane Band,” J. Quant. Spectrosc. Radiat. Transfer 11, 69 (1971).
[CrossRef]

1969

R. L. Barger, J. L. Hall, “Pressure Shift and Broadening of Methane Line at 3.39 μ Studied by Laser-Saturated Molecular Absorption,” Phys. Rev. Lett. 22, 4 (1969).
[CrossRef]

Agresta, D. L.

Ballard, J.

J. Ballard, W. B. Johnson, “Self-Broadened Widths and Absolute Strengths of 12CH4 Lines in the 1310–1370-cm−1 Region,” J. Quant. Spectrosc. Radiat. Transfer 36, 365 (1986).
[CrossRef]

Barger, R. L.

R. L. Barger, J. L. Hall, “Pressure Shift and Broadening of Methane Line at 3.39 μ Studied by Laser-Saturated Molecular Absorption,” Phys. Rev. Lett. 22, 4 (1969).
[CrossRef]

Beckwith, P. H.

P. H. Beckwith, D. J. Danagher, J. Reid, “Linewidths and Linestrengths in the ν2 Band of NH3 as Measured with a Tunable Diode Laser,” J. Mol. Spectrosc. 121, 209 (1987).
[CrossRef]

Benner, D. C.

V. M. Devi, C. P. Rinsland, M. A. H. Smith, D. C. Benner, “Measurements of 12CH4ν4 Band Halfwidths Using a Tunable Diode Laser System and a Fourier Transform Spectrometer,” Appl. Opt. 24, 2788 (1985).
[CrossRef]

C. P. Rinsland, D. C. Benner, D. J. Richardson, R. A. Toth, “Absolute Intensity Measurements of the (1110)II ← (00°0) Band of 12C16O2 at 5.2 μm,” Appl. Opt. 22, 3805 (1983).
[CrossRef] [PubMed]

C. P. Rinsland, D. C. Benner, V. M. Devi, P. S. Ferry, C. H. Sutton, D. J. Richardson, “Atlas of High Resolution Infrared Spectra of Carbon Dioxide: Feb. 1984 Edition,” NASA Tech. Memo. 85764 (NASA Langley Research Center, Hampton, VA, Feb.1984), 468 pp.

D. C. Benner, C. P. Rinsland, V. M. Devi, “Air-Broadened Halfwidths in the ν3 Band of 12CH4,” presented at Forty-first Symposium on Molecular Spectroscopy, 17 June 1986, Columbus, OH (1986), paper TB5.

Blum, F. A.

F. A. Blum, K. W. Nill, P. L. Kelley, A. R. Calawa, T. C. Harman, “Tunable Infrared Laser Spectroscopy of Atmospheric Water Vapor,” Science 177, 694 (1972).
[CrossRef] [PubMed]

Brown, L. R.

Calawa, A. R.

R. S. Eng, P. L. Kelley, A. R. Calawa, T. C. Harman, K. W. Nill, “Tunable Diode Laser Measurements of Water Vapour Absorption Line Parameters,” Mol. Phys. 28, 653 (1974).
[CrossRef]

R. S. Eng, P. L. Kelley, A. Mooradian, A. R. Calawa, T. C. Harman, “Tunable Laser Measurements of Water Vapor Transitions in the Vicinity of 5 μm,” Chem. Phys. Lett. 19, 524 (1973).
[CrossRef]

R. S. Eng, A. R. Calawa, T. C. Harman, P. L. Kelley, A. Javan, “Collisional Narrowing of Infrared Water-Vapor Transitions,” Appl. Phys. Lett. 21, 303 (1972).
[CrossRef]

F. A. Blum, K. W. Nill, P. L. Kelley, A. R. Calawa, T. C. Harman, “Tunable Infrared Laser Spectroscopy of Atmospheric Water Vapor,” Science 177, 694 (1972).
[CrossRef] [PubMed]

Camy-Peyret, C.

J.-M. Flaud, C. Camy-Peyret, R. A. Toth, Selected Constants: Water Vapour Line Parameters from Microwave to Medium Infrared (Pergamon, Oxford, 1981).

Chedin, A.

A. Chedin, N. Husson, N. A. Scott, D. Gautier, “ν4 Band of Methane (12CH4 and 13CH4). Line Parameters and Evaluation of Jovian Atmospheric Transmission at 7.7 μm,” J. Mol. Spectrosc. 71, 343 (1978).
[CrossRef]

Danagher, D. J.

P. H. Beckwith, D. J. Danagher, J. Reid, “Linewidths and Linestrengths in the ν2 Band of NH3 as Measured with a Tunable Diode Laser,” J. Mol. Spectrosc. 121, 209 (1987).
[CrossRef]

Das, P. P.

V. M. Devi, B. Fridovich, D. G. S. Snyder, G. D. Jones, P. P. Das, “Tunable Diode Laser Measurements of Intensities and Lorentz Broadening Coefficients of Lines in the ν2 Band of 12CH4,” J. Quant. Spectrosc. Radiat. Transfer 29, 45 (1983).
[CrossRef]

Davies, R. W.

R. R. Gamache, R. W. Davies, “Theoretical Calculations of N2-Broadened Halfwidths of H2O Using Quantum Fourier Transform Theory,” Appl. Opt. 22, 4013 (1983).
[CrossRef] [PubMed]

R. W. Davies, B. A. Oli, “Theoretical Calculations of H2O Linewidths and Pressure Shifts: Comparison of the Anderson Theory with Quantum Many-Body Theory for N2 and Air-Broadened Lines,” J. Quant. Spectrosc. Radiat. Transfer 20, 95 (1978).
[CrossRef]

Devi, V. M.

V. M. Devi, C. P. Rinsland, M. A. H. Smith, D. C. Benner, “Measurements of 12CH4ν4 Band Halfwidths Using a Tunable Diode Laser System and a Fourier Transform Spectrometer,” Appl. Opt. 24, 2788 (1985).
[CrossRef]

V. M. Devi, B. Fridovich, D. G. S. Snyder, G. D. Jones, P. P. Das, “Tunable Diode Laser Measurements of Intensities and Lorentz Broadening Coefficients of Lines in the ν2 Band of 12CH4,” J. Quant. Spectrosc. Radiat. Transfer 29, 45 (1983).
[CrossRef]

V. M. Devi, B. Fridovich, G. D. Jones, D. G. S. Snyder, “Strengths and Lorentz Broadening Coefficients for Spectral Lines in the ν3 and ν2 + ν4 Bands of 12CH4 and 13CH4,” J. Mol. Spectrosc. 97, 333 (1983).
[CrossRef]

C. P. Rinsland, D. C. Benner, V. M. Devi, P. S. Ferry, C. H. Sutton, D. J. Richardson, “Atlas of High Resolution Infrared Spectra of Carbon Dioxide: Feb. 1984 Edition,” NASA Tech. Memo. 85764 (NASA Langley Research Center, Hampton, VA, Feb.1984), 468 pp.

D. C. Benner, C. P. Rinsland, V. M. Devi, “Air-Broadened Halfwidths in the ν3 Band of 12CH4,” presented at Forty-first Symposium on Molecular Spectroscopy, 17 June 1986, Columbus, OH (1986), paper TB5.

Eng, R. S.

R. S. Eng, P. L. Kelley, A. R. Calawa, T. C. Harman, K. W. Nill, “Tunable Diode Laser Measurements of Water Vapour Absorption Line Parameters,” Mol. Phys. 28, 653 (1974).
[CrossRef]

R. S. Eng, P. L. Kelley, A. Mooradian, A. R. Calawa, T. C. Harman, “Tunable Laser Measurements of Water Vapor Transitions in the Vicinity of 5 μm,” Chem. Phys. Lett. 19, 524 (1973).
[CrossRef]

R. S. Eng, A. R. Calawa, T. C. Harman, P. L. Kelley, A. Javan, “Collisional Narrowing of Infrared Water-Vapor Transitions,” Appl. Phys. Lett. 21, 303 (1972).
[CrossRef]

Farmer, C. B.

Ferry, P. S.

C. P. Rinsland, D. C. Benner, V. M. Devi, P. S. Ferry, C. H. Sutton, D. J. Richardson, “Atlas of High Resolution Infrared Spectra of Carbon Dioxide: Feb. 1984 Edition,” NASA Tech. Memo. 85764 (NASA Langley Research Center, Hampton, VA, Feb.1984), 468 pp.

Flaud, J.-M.

J.-M. Flaud, C. Camy-Peyret, R. A. Toth, Selected Constants: Water Vapour Line Parameters from Microwave to Medium Infrared (Pergamon, Oxford, 1981).

Fox, K.

K. Fox, “Symmetry-Dependent Broadening Parameters for Methane,” J. Chem. Phys. 80, 1367 (1984).
[CrossRef]

G. D. T. Tejwani, P. Varanasi, K. Fox, “Collision-Broadened Linewidths of Tetrahedral Molecules—II. Computations for CH4 Lines Broadened by N2, O2, He, Ne and Ar,” J. Quant. Spectrosc. Radiat. Transfer 15, 243 (1975).
[CrossRef]

G. D. T. Tejwani, K. Fox, “Calculated Linewidths for CH4 Broadened by N2 and O2,” J. Chem. Phys. 60, 2021 (1974).
[CrossRef]

Fridovich, B.

V. M. Devi, B. Fridovich, D. G. S. Snyder, G. D. Jones, P. P. Das, “Tunable Diode Laser Measurements of Intensities and Lorentz Broadening Coefficients of Lines in the ν2 Band of 12CH4,” J. Quant. Spectrosc. Radiat. Transfer 29, 45 (1983).
[CrossRef]

V. M. Devi, B. Fridovich, G. D. Jones, D. G. S. Snyder, “Strengths and Lorentz Broadening Coefficients for Spectral Lines in the ν3 and ν2 + ν4 Bands of 12CH4 and 13CH4,” J. Mol. Spectrosc. 97, 333 (1983).
[CrossRef]

M. A. H. Smith, C. P. Rinsland, B. Fridovich, K. N. Rao, “Intensities and Collision Broadening Parameters from Infrared Spectra,” in Molecular Spectroscopy: Modern Research, Vol. 3, K. N. Rao, Ed. (Academic, Orlando, 1985), Chap. 3.

Gamache, R. R.

Gautier, D.

A. Chedin, N. Husson, N. A. Scott, D. Gautier, “ν4 Band of Methane (12CH4 and 13CH4). Line Parameters and Evaluation of Jovian Atmospheric Transmission at 7.7 μm,” J. Mol. Spectrosc. 71, 343 (1978).
[CrossRef]

Giver, L. P.

P. Varanasi, L. P. Giver, F. P. J. Valero, “Thermal Infrared Lines of Methane Broadened by Nitrogen at Low Temperatures,” J. Quant. Spectrosc. Radiat. Transfer 30, 481 (1983).
[CrossRef]

Hall, J. L.

R. L. Barger, J. L. Hall, “Pressure Shift and Broadening of Methane Line at 3.39 μ Studied by Laser-Saturated Molecular Absorption,” Phys. Rev. Lett. 22, 4 (1969).
[CrossRef]

Hanson, R. K.

Harman, T. C.

R. S. Eng, P. L. Kelley, A. R. Calawa, T. C. Harman, K. W. Nill, “Tunable Diode Laser Measurements of Water Vapour Absorption Line Parameters,” Mol. Phys. 28, 653 (1974).
[CrossRef]

R. S. Eng, P. L. Kelley, A. Mooradian, A. R. Calawa, T. C. Harman, “Tunable Laser Measurements of Water Vapor Transitions in the Vicinity of 5 μm,” Chem. Phys. Lett. 19, 524 (1973).
[CrossRef]

R. S. Eng, A. R. Calawa, T. C. Harman, P. L. Kelley, A. Javan, “Collisional Narrowing of Infrared Water-Vapor Transitions,” Appl. Phys. Lett. 21, 303 (1972).
[CrossRef]

F. A. Blum, K. W. Nill, P. L. Kelley, A. R. Calawa, T. C. Harman, “Tunable Infrared Laser Spectroscopy of Atmospheric Water Vapor,” Science 177, 694 (1972).
[CrossRef] [PubMed]

Hirono, M.

G. Yamamoto, M. Hirono, “Rotational Line Width of Methane,” J. Quant. Spectrosc. Radiat. Transfer 11, 1537 (1971).
[CrossRef]

Husson, N.

A. Chedin, N. Husson, N. A. Scott, D. Gautier, “ν4 Band of Methane (12CH4 and 13CH4). Line Parameters and Evaluation of Jovian Atmospheric Transmission at 7.7 μm,” J. Mol. Spectrosc. 71, 343 (1978).
[CrossRef]

Javan, A.

R. S. Eng, A. R. Calawa, T. C. Harman, P. L. Kelley, A. Javan, “Collisional Narrowing of Infrared Water-Vapor Transitions,” Appl. Phys. Lett. 21, 303 (1972).
[CrossRef]

Johnson, W. B.

J. Ballard, W. B. Johnson, “Self-Broadened Widths and Absolute Strengths of 12CH4 Lines in the 1310–1370-cm−1 Region,” J. Quant. Spectrosc. Radiat. Transfer 36, 365 (1986).
[CrossRef]

Jones, G. D.

V. M. Devi, B. Fridovich, D. G. S. Snyder, G. D. Jones, P. P. Das, “Tunable Diode Laser Measurements of Intensities and Lorentz Broadening Coefficients of Lines in the ν2 Band of 12CH4,” J. Quant. Spectrosc. Radiat. Transfer 29, 45 (1983).
[CrossRef]

V. M. Devi, B. Fridovich, G. D. Jones, D. G. S. Snyder, “Strengths and Lorentz Broadening Coefficients for Spectral Lines in the ν3 and ν2 + ν4 Bands of 12CH4 and 13CH4,” J. Mol. Spectrosc. 97, 333 (1983).
[CrossRef]

Kelley, P. L.

R. S. Eng, P. L. Kelley, A. R. Calawa, T. C. Harman, K. W. Nill, “Tunable Diode Laser Measurements of Water Vapour Absorption Line Parameters,” Mol. Phys. 28, 653 (1974).
[CrossRef]

R. S. Eng, P. L. Kelley, A. Mooradian, A. R. Calawa, T. C. Harman, “Tunable Laser Measurements of Water Vapor Transitions in the Vicinity of 5 μm,” Chem. Phys. Lett. 19, 524 (1973).
[CrossRef]

R. S. Eng, A. R. Calawa, T. C. Harman, P. L. Kelley, A. Javan, “Collisional Narrowing of Infrared Water-Vapor Transitions,” Appl. Phys. Lett. 21, 303 (1972).
[CrossRef]

F. A. Blum, K. W. Nill, P. L. Kelley, A. R. Calawa, T. C. Harman, “Tunable Infrared Laser Spectroscopy of Atmospheric Water Vapor,” Science 177, 694 (1972).
[CrossRef] [PubMed]

Margolis, J. S.

J. S. Margolis, “Self-Broadened Half-Widths and Pressure Shifts for the R-Branch J-Manifolds of the 3ν3 Methane Band,” J. Quant. Spectrosc. Radiat. Transfer 11, 69 (1971).
[CrossRef]

Mooradian, A.

R. S. Eng, P. L. Kelley, A. Mooradian, A. R. Calawa, T. C. Harman, “Tunable Laser Measurements of Water Vapor Transitions in the Vicinity of 5 μm,” Chem. Phys. Lett. 19, 524 (1973).
[CrossRef]

Nill, K. W.

R. S. Eng, P. L. Kelley, A. R. Calawa, T. C. Harman, K. W. Nill, “Tunable Diode Laser Measurements of Water Vapour Absorption Line Parameters,” Mol. Phys. 28, 653 (1974).
[CrossRef]

F. A. Blum, K. W. Nill, P. L. Kelley, A. R. Calawa, T. C. Harman, “Tunable Infrared Laser Spectroscopy of Atmospheric Water Vapor,” Science 177, 694 (1972).
[CrossRef] [PubMed]

Oli, B. A.

R. W. Davies, B. A. Oli, “Theoretical Calculations of H2O Linewidths and Pressure Shifts: Comparison of the Anderson Theory with Quantum Many-Body Theory for N2 and Air-Broadened Lines,” J. Quant. Spectrosc. Radiat. Transfer 20, 95 (1978).
[CrossRef]

Pine, A. S.

A. S. Pine, “Precision Collisional Lineshapes by Difference-Frequency Laser Spectroscopy,” Proc. Soc. Photo-Opt. Instrum. Eng. 277, 64 (1981).

A. S. Pine, “Collisional Narrowing of HF Fundamental Band Spectral Lines by Neon and Argon,” J. Mol. Spectrosc. 82, 435 (1980).
[CrossRef]

A. S. Pine, “High-Resolution Methane ν3-Band Spectra Using a Stabilized Tunable Difference-Frequency Laser System,” J. Opt. Soc. Am. 66, 97 (1976).
[CrossRef]

Rao, K. N.

M. A. H. Smith, C. P. Rinsland, B. Fridovich, K. N. Rao, “Intensities and Collision Broadening Parameters from Infrared Spectra,” in Molecular Spectroscopy: Modern Research, Vol. 3, K. N. Rao, Ed. (Academic, Orlando, 1985), Chap. 3.

Reid, J.

P. H. Beckwith, D. J. Danagher, J. Reid, “Linewidths and Linestrengths in the ν2 Band of NH3 as Measured with a Tunable Diode Laser,” J. Mol. Spectrosc. 121, 209 (1987).
[CrossRef]

Richardson, D. J.

C. P. Rinsland, D. C. Benner, D. J. Richardson, R. A. Toth, “Absolute Intensity Measurements of the (1110)II ← (00°0) Band of 12C16O2 at 5.2 μm,” Appl. Opt. 22, 3805 (1983).
[CrossRef] [PubMed]

C. P. Rinsland, D. C. Benner, V. M. Devi, P. S. Ferry, C. H. Sutton, D. J. Richardson, “Atlas of High Resolution Infrared Spectra of Carbon Dioxide: Feb. 1984 Edition,” NASA Tech. Memo. 85764 (NASA Langley Research Center, Hampton, VA, Feb.1984), 468 pp.

Rinsland, C. P.

L. R. Brown, C. B. Farmer, C. P. Rinsland, R. A. Toth, “Molecular Line Parameters for the Atmospheric Trace Molecule Spectroscopy Experiment,” Appl. Opt. 26, 5154 (1987).

V. M. Devi, C. P. Rinsland, M. A. H. Smith, D. C. Benner, “Measurements of 12CH4ν4 Band Halfwidths Using a Tunable Diode Laser System and a Fourier Transform Spectrometer,” Appl. Opt. 24, 2788 (1985).
[CrossRef]

C. P. Rinsland, D. C. Benner, D. J. Richardson, R. A. Toth, “Absolute Intensity Measurements of the (1110)II ← (00°0) Band of 12C16O2 at 5.2 μm,” Appl. Opt. 22, 3805 (1983).
[CrossRef] [PubMed]

C. P. Rinsland, D. C. Benner, V. M. Devi, P. S. Ferry, C. H. Sutton, D. J. Richardson, “Atlas of High Resolution Infrared Spectra of Carbon Dioxide: Feb. 1984 Edition,” NASA Tech. Memo. 85764 (NASA Langley Research Center, Hampton, VA, Feb.1984), 468 pp.

M. A. H. Smith, C. P. Rinsland, B. Fridovich, K. N. Rao, “Intensities and Collision Broadening Parameters from Infrared Spectra,” in Molecular Spectroscopy: Modern Research, Vol. 3, K. N. Rao, Ed. (Academic, Orlando, 1985), Chap. 3.

D. C. Benner, C. P. Rinsland, V. M. Devi, “Air-Broadened Halfwidths in the ν3 Band of 12CH4,” presented at Forty-first Symposium on Molecular Spectroscopy, 17 June 1986, Columbus, OH (1986), paper TB5.

Rothman, L. S.

Scott, N. A.

A. Chedin, N. Husson, N. A. Scott, D. Gautier, “ν4 Band of Methane (12CH4 and 13CH4). Line Parameters and Evaluation of Jovian Atmospheric Transmission at 7.7 μm,” J. Mol. Spectrosc. 71, 343 (1978).
[CrossRef]

Shaw, J. H.

Smith, M. A. H.

V. M. Devi, C. P. Rinsland, M. A. H. Smith, D. C. Benner, “Measurements of 12CH4ν4 Band Halfwidths Using a Tunable Diode Laser System and a Fourier Transform Spectrometer,” Appl. Opt. 24, 2788 (1985).
[CrossRef]

M. A. H. Smith, C. P. Rinsland, B. Fridovich, K. N. Rao, “Intensities and Collision Broadening Parameters from Infrared Spectra,” in Molecular Spectroscopy: Modern Research, Vol. 3, K. N. Rao, Ed. (Academic, Orlando, 1985), Chap. 3.

Snyder, D. G. S.

V. M. Devi, B. Fridovich, G. D. Jones, D. G. S. Snyder, “Strengths and Lorentz Broadening Coefficients for Spectral Lines in the ν3 and ν2 + ν4 Bands of 12CH4 and 13CH4,” J. Mol. Spectrosc. 97, 333 (1983).
[CrossRef]

V. M. Devi, B. Fridovich, D. G. S. Snyder, G. D. Jones, P. P. Das, “Tunable Diode Laser Measurements of Intensities and Lorentz Broadening Coefficients of Lines in the ν2 Band of 12CH4,” J. Quant. Spectrosc. Radiat. Transfer 29, 45 (1983).
[CrossRef]

Sutton, C. H.

C. P. Rinsland, D. C. Benner, V. M. Devi, P. S. Ferry, C. H. Sutton, D. J. Richardson, “Atlas of High Resolution Infrared Spectra of Carbon Dioxide: Feb. 1984 Edition,” NASA Tech. Memo. 85764 (NASA Langley Research Center, Hampton, VA, Feb.1984), 468 pp.

Tejwani, G. D. T.

G. D. T. Tejwani, P. Varanasi, K. Fox, “Collision-Broadened Linewidths of Tetrahedral Molecules—II. Computations for CH4 Lines Broadened by N2, O2, He, Ne and Ar,” J. Quant. Spectrosc. Radiat. Transfer 15, 243 (1975).
[CrossRef]

G. D. T. Tejwani, K. Fox, “Calculated Linewidths for CH4 Broadened by N2 and O2,” J. Chem. Phys. 60, 2021 (1974).
[CrossRef]

P. Varanasi, G. D. T. Tejwani, “Experimental and Theoretical Studies on Collision-Broadened Lines in the ν4-Fundamental of Methane,” J. Quant. Spectrosc. Radiat. Transfer 12, 849 (1972).
[CrossRef]

G. D. T. Tejwani, P. Varanasi, “Calculation of Collision-Broadened Linewidths in the Infrared Bands of Methane,” J. Chem. Phys. 55, 1075 (1971).
[CrossRef]

Toth, R. A.

Tu, N.

Valero, F. P. J.

P. Varanasi, L. P. Giver, F. P. J. Valero, “Thermal Infrared Lines of Methane Broadened by Nitrogen at Low Temperatures,” J. Quant. Spectrosc. Radiat. Transfer 30, 481 (1983).
[CrossRef]

Varanasi, P.

P. Varanasi, L. P. Giver, F. P. J. Valero, “Thermal Infrared Lines of Methane Broadened by Nitrogen at Low Temperatures,” J. Quant. Spectrosc. Radiat. Transfer 30, 481 (1983).
[CrossRef]

G. D. T. Tejwani, P. Varanasi, K. Fox, “Collision-Broadened Linewidths of Tetrahedral Molecules—II. Computations for CH4 Lines Broadened by N2, O2, He, Ne and Ar,” J. Quant. Spectrosc. Radiat. Transfer 15, 243 (1975).
[CrossRef]

P. Varanasi, “Collision-Broadened Line Widths of Tetrahedral Molecules-I. Theoretical Formulation,” J. Quant. Spectrosc. Radiat. Transfer 14, 995 (1974).
[CrossRef]

P. Varanasi, G. D. T. Tejwani, “Experimental and Theoretical Studies on Collision-Broadened Lines in the ν4-Fundamental of Methane,” J. Quant. Spectrosc. Radiat. Transfer 12, 849 (1972).
[CrossRef]

G. D. T. Tejwani, P. Varanasi, “Calculation of Collision-Broadened Linewidths in the Infrared Bands of Methane,” J. Chem. Phys. 55, 1075 (1971).
[CrossRef]

P. Varanasi, “Collision-Broadened Half-Widths and Shapes of Methane Lines,” J. Quant. Spectrosc. Radiat. Transfer 11, 1711 (1971).
[CrossRef]

Varghese, P. L.

Yamamoto, G.

G. Yamamoto, M. Hirono, “Rotational Line Width of Methane,” J. Quant. Spectrosc. Radiat. Transfer 11, 1537 (1971).
[CrossRef]

Appl. Opt.

Appl. Phys. Lett.

R. S. Eng, A. R. Calawa, T. C. Harman, P. L. Kelley, A. Javan, “Collisional Narrowing of Infrared Water-Vapor Transitions,” Appl. Phys. Lett. 21, 303 (1972).
[CrossRef]

Chem. Phys. Lett.

R. S. Eng, P. L. Kelley, A. Mooradian, A. R. Calawa, T. C. Harman, “Tunable Laser Measurements of Water Vapor Transitions in the Vicinity of 5 μm,” Chem. Phys. Lett. 19, 524 (1973).
[CrossRef]

J. Chem. Phys.

G. D. T. Tejwani, K. Fox, “Calculated Linewidths for CH4 Broadened by N2 and O2,” J. Chem. Phys. 60, 2021 (1974).
[CrossRef]

G. D. T. Tejwani, P. Varanasi, “Calculation of Collision-Broadened Linewidths in the Infrared Bands of Methane,” J. Chem. Phys. 55, 1075 (1971).
[CrossRef]

K. Fox, “Symmetry-Dependent Broadening Parameters for Methane,” J. Chem. Phys. 80, 1367 (1984).
[CrossRef]

J. Mol. Spectrosc.

P. H. Beckwith, D. J. Danagher, J. Reid, “Linewidths and Linestrengths in the ν2 Band of NH3 as Measured with a Tunable Diode Laser,” J. Mol. Spectrosc. 121, 209 (1987).
[CrossRef]

V. M. Devi, B. Fridovich, G. D. Jones, D. G. S. Snyder, “Strengths and Lorentz Broadening Coefficients for Spectral Lines in the ν3 and ν2 + ν4 Bands of 12CH4 and 13CH4,” J. Mol. Spectrosc. 97, 333 (1983).
[CrossRef]

A. S. Pine, “Collisional Narrowing of HF Fundamental Band Spectral Lines by Neon and Argon,” J. Mol. Spectrosc. 82, 435 (1980).
[CrossRef]

A. Chedin, N. Husson, N. A. Scott, D. Gautier, “ν4 Band of Methane (12CH4 and 13CH4). Line Parameters and Evaluation of Jovian Atmospheric Transmission at 7.7 μm,” J. Mol. Spectrosc. 71, 343 (1978).
[CrossRef]

J. Opt. Soc. Am.

J. Opt. Soc. Am. B

J. Quant. Spectrosc. Radiat. Transfer

P. Varanasi, L. P. Giver, F. P. J. Valero, “Thermal Infrared Lines of Methane Broadened by Nitrogen at Low Temperatures,” J. Quant. Spectrosc. Radiat. Transfer 30, 481 (1983).
[CrossRef]

V. M. Devi, B. Fridovich, D. G. S. Snyder, G. D. Jones, P. P. Das, “Tunable Diode Laser Measurements of Intensities and Lorentz Broadening Coefficients of Lines in the ν2 Band of 12CH4,” J. Quant. Spectrosc. Radiat. Transfer 29, 45 (1983).
[CrossRef]

G. D. T. Tejwani, P. Varanasi, K. Fox, “Collision-Broadened Linewidths of Tetrahedral Molecules—II. Computations for CH4 Lines Broadened by N2, O2, He, Ne and Ar,” J. Quant. Spectrosc. Radiat. Transfer 15, 243 (1975).
[CrossRef]

P. Varanasi, “Collision-Broadened Line Widths of Tetrahedral Molecules-I. Theoretical Formulation,” J. Quant. Spectrosc. Radiat. Transfer 14, 995 (1974).
[CrossRef]

G. Yamamoto, M. Hirono, “Rotational Line Width of Methane,” J. Quant. Spectrosc. Radiat. Transfer 11, 1537 (1971).
[CrossRef]

P. Varanasi, “Collision-Broadened Half-Widths and Shapes of Methane Lines,” J. Quant. Spectrosc. Radiat. Transfer 11, 1711 (1971).
[CrossRef]

P. Varanasi, G. D. T. Tejwani, “Experimental and Theoretical Studies on Collision-Broadened Lines in the ν4-Fundamental of Methane,” J. Quant. Spectrosc. Radiat. Transfer 12, 849 (1972).
[CrossRef]

J. Ballard, W. B. Johnson, “Self-Broadened Widths and Absolute Strengths of 12CH4 Lines in the 1310–1370-cm−1 Region,” J. Quant. Spectrosc. Radiat. Transfer 36, 365 (1986).
[CrossRef]

R. W. Davies, B. A. Oli, “Theoretical Calculations of H2O Linewidths and Pressure Shifts: Comparison of the Anderson Theory with Quantum Many-Body Theory for N2 and Air-Broadened Lines,” J. Quant. Spectrosc. Radiat. Transfer 20, 95 (1978).
[CrossRef]

J. S. Margolis, “Self-Broadened Half-Widths and Pressure Shifts for the R-Branch J-Manifolds of the 3ν3 Methane Band,” J. Quant. Spectrosc. Radiat. Transfer 11, 69 (1971).
[CrossRef]

Mol. Phys.

R. S. Eng, P. L. Kelley, A. R. Calawa, T. C. Harman, K. W. Nill, “Tunable Diode Laser Measurements of Water Vapour Absorption Line Parameters,” Mol. Phys. 28, 653 (1974).
[CrossRef]

Phys. Rev. Lett.

R. L. Barger, J. L. Hall, “Pressure Shift and Broadening of Methane Line at 3.39 μ Studied by Laser-Saturated Molecular Absorption,” Phys. Rev. Lett. 22, 4 (1969).
[CrossRef]

Proc. Soc. Photo-Opt. Instrum. Eng.

A. S. Pine, “Precision Collisional Lineshapes by Difference-Frequency Laser Spectroscopy,” Proc. Soc. Photo-Opt. Instrum. Eng. 277, 64 (1981).

Science

F. A. Blum, K. W. Nill, P. L. Kelley, A. R. Calawa, T. C. Harman, “Tunable Infrared Laser Spectroscopy of Atmospheric Water Vapor,” Science 177, 694 (1972).
[CrossRef] [PubMed]

Other

M. A. H. Smith, C. P. Rinsland, B. Fridovich, K. N. Rao, “Intensities and Collision Broadening Parameters from Infrared Spectra,” in Molecular Spectroscopy: Modern Research, Vol. 3, K. N. Rao, Ed. (Academic, Orlando, 1985), Chap. 3.

J.-M. Flaud, C. Camy-Peyret, R. A. Toth, Selected Constants: Water Vapour Line Parameters from Microwave to Medium Infrared (Pergamon, Oxford, 1981).

C. P. Rinsland, D. C. Benner, V. M. Devi, P. S. Ferry, C. H. Sutton, D. J. Richardson, “Atlas of High Resolution Infrared Spectra of Carbon Dioxide: Feb. 1984 Edition,” NASA Tech. Memo. 85764 (NASA Langley Research Center, Hampton, VA, Feb.1984), 468 pp.

D. C. Benner, C. P. Rinsland, V. M. Devi, “Air-Broadened Halfwidths in the ν3 Band of 12CH4,” presented at Forty-first Symposium on Molecular Spectroscopy, 17 June 1986, Columbus, OH (1986), paper TB5.

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Figures (11)

Fig. 1
Fig. 1

Compressed plot covering the ν4 band region of methane obtained with 551.0 Torr of a mixture of 1.005% natural methane in dry air in a 25-cm absorption path at 25.2°C. The normalization of the measured intensities is arbitrary; the zero signal level is shown at the lower left.

Fig. 2
Fig. 2

The R2 to R5 ν4 band manifold region of the spectrum plotted in Fig. 1. Strong residual water vapor lines are marked with solid circles; the narrow components of these lines show sidelobes characteristic of the interferometer line shape function.

Fig. 3
Fig. 3

Example of a least-squares fit to the laboratory data. The measured spectrum (lower plot) was recorded with 425.0 Torr of a 1.005% natural methane in dry air mixture in a 5-cm absorption path at 25.5°C. The residuals (observed minus calculated) are plotted in the upper panel on an expanded vertical scale and are expressed as a percentage of the peak measured intensity in the fitted region. Tick marks above the observed spectrum indicate the positions of spectral lines included in the calculations. Lines of H2O are marked beneath the spectrum with a solid circle.

Fig. 4
Fig. 4

Plots of calibrated line position vs total sample pressure of lean mixtures of CH4 in dry air for two lines of the ν4 band of 12CH4. The unshifted line position and pressure shift coefficient correspond, respectively, to the ordinate intercept and slope on the least-squares fit (solid line passing close to the measurements).

Fig. 5
Fig. 5

Plot of measured Lorentz halfwidth vs total sample pressure of lean mixtures of CH4 in dry air for the permitted P8 F12 ← F22 line of the ν4 band of 12CH4 near 1253.3488 cm−1. The measured halfwidth coefficient corresponds to the slope of the least-squares fit (solid line passing close to the measurements and through the origin).

Fig. 6
Fig. 6

Measured air-broadened Lorentz halfwidth coefficient vs |m| (defined in text) for (a) F-species lines, (b) A-species lines, and (c) E-species lines. Open and solid symbols represent permitted and forbidden transitions, respectively. The air-broadened halfwidth coefficients assumed in the 1986 HITRAN compilation3 are also shown for 8 ≤ |m| ≤ 19.

Fig. 7
Fig. 7

Measured air-broadened Lorentz halfwidth coefficients of F-species lines at (b) J″ = 15 and (a) J″ = 17 vs lower state energy. Open and solid symbols represent permitted and forbidden lines, respectively.

Fig. 8
Fig. 8

Air-broadened Lorentz halfwidth coefficients vs J″ for (a) A21 ← A11 and (b) A11 ← A21 transitions measured in both the P and R branches of the ν4 band. Transitions measured only in the R branch or only in the P branch have been omitted. Despite the measurement gaps, solid lines connect adjacent measurements to help distinguish the R-branch from the P-branch data.

Fig. 9
Fig. 9

Ratio of the air-broadened Lorentz halfwidth coefficient to the N2-broadened Lorentz halfwidth coefficient vs |m| (defined in text). The horizontal dashed line indicates a ratio of unity.

Fig. 10
Fig. 10

Ratio of air-broadened Lorentz halfwidth coefficient in the ν4 band to the value measured for the same transition in the ν3 band vs J″. Error limits are 2σ uncertainties. The abscissa values have been shifted slightly for clarity.

Fig. 11
Fig. 11

Measured air-broadened pressure-shift coefficient vs |m| (defined in text) for (a) F-species lines, (b) A-species lines, and (c) E-species lines. Open and solid symbols represent permitted and forbidden transitions, respectively.

Tables (11)

Tables Icon

Table I Experimental Conditions

Tables Icon

Table II Halfwidth and Pressure Shift Coefficientsa Measured in the ν4 Band of 12CH4

Tables Icon

Table III Halfwidth and Pressure Shift Coefficientsa Measured in the ν2 Band of 12CH4

Tables Icon

Table IV Comparison of Air-Broadened Halfwidth Coefficients (cm−1 atm−1 at 296 K) Measured in Both the R and P Branches of the ν4 Band

Tables Icon

Table V Mean and Standard Deviation of the Ratio of R- branch to P- branch Air-Broadened Halfwidth Coefficients

Tables Icon

Table VI Mean and Standard Deviation of Halfwidth Coefficient (in cm−1 atm−1 at 296 K) vs |m| Derived from Air-Broadening Measurements in the ν4 and ν2 Bands of 12CH4

Tables Icon

Table VII Comparison Between Air-Broadened Halfwidth Coefficients (cm−1 atm−1 at 296 K) Measured in the R Branch of the ν4 Band in this Study and the Calculated Values of Tejwani et al.25

Tables Icon

Table VIII Mean and Standard Deviation of Halfwidth Coefficients Obtained In this Study Ratloed to Previously Reported Values

Tables Icon

Table IX Comparison of ν4 and ν3 Band Air-Broadened Halfwidth Coefficients (cm−1 atm−1 at 296 K) Determined from McMath FTS Spectraa

Tables Icon

Table X Mean and Standard Deviation of Pressure Shift Coefficients (in cm−1 atm−1) vs |m| Derived from Room Temperature Air-Broadening Measurements in the ν4 and ν2 Bands of 12CH4

Tables Icon

Table XI Comparison of Measured and HITRAN 86 Line Positionsa

Equations (2)

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b L = b L 0 p
ν L = ν 0 + δ 0 p

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