Line parameters including temperature dependences of self- and air-broadened line shapes of 12 C 16 O 2 : 1.6-μm region

Abstract Pressure-broadened line shapes in the 30013←00001 (ν1+4 ν 2 0 +ν3) band of 12C16O2 at 6228 cm−1 are reanalyzed using new spectra recorded with sample temperatures down to 170 K. High resolution, high signal-to-noise (S/N) laboratory measurements of line shapes (Lorentz air- and self-broadened half-width coefficients, pressure-shift coefficients and off-diagonal relaxation matrix element coefficients) as a function of gas sample temperatures for various pressures and volume mixing ratios are presented. The spectra were recorded using two different Fourier transform spectrometers (FTS): (1) the McMath-Pierce FTS located at the National Solar Observatory on Kitt Peak, Arizona (and reported in Devi et al., J Mol Spectrosc 2007;245:52-80) and, (2) the Bruker IFS-125HR FTS at the Jet Propulsion Laboratory in Pasadena, California. The 19 spectra taken at Kitt Peak were all recorded near room temperature while the 27 Bruker spectra were acquired both at room temperature and colder temperatures (170-296 K). Various spectral resolutions (0.004–0.011 cm−1), absorption path lengths (2.46–121 m) and CO2 samples (natural and 12C-enriched) were included in the dataset. To maximize the accuracies of the various retrieved line parameters, a multispectrum nonlinear least squares spectrum fitting software program was used to adjust the ro-vibrational constants (G,B,D etc.) and intensity parameters (including Herman-Wallis terms) instead of directly measuring the individual line positions and intensities. To minimize systematic residuals, line mixing (via off-diagonal relaxation matrix elements) and quadratic speed dependence parameters were included in the analysis. Contributions from other weakly absorbing bands: the 30013←00001 and 30012←00001 bands of 13C16O2, the 30013←00001 band of 12C16O18O, hot bands 31113←01101 and 32212←02201 of 12C16O2, as well as the 40013←10001 and the 40014←10002 bands of 12C16O2, present within the fitted interval were also measured. Results from previous works and new calculations are compared to present measurements, where appropriate.

[1]  V. Malathy Devi,et al.  Line strengths of 12C16O2: 4550–7000 cm−1 , 2006 .

[2]  V. Malathy Devi,et al.  Spectroscopic database of CO2 line parameters: 4300–7000 cm−1 , 2008 .

[3]  Laurence S. Rothman,et al.  Updated database plus software for line-mixing in CO2 infrared spectra and their test using laboratory spectra in the 1.5–2.3 μm region , 2010 .

[4]  Charles Chackerian,et al.  Collisional Line Mixing , 1992 .

[5]  Bertrand Parvitte,et al.  A complete study of the line intensities of four bands of CO2 around 1.6 and 2.0 μm: A comparison between Fourier transform and diode laser measurements , 2006 .

[6]  Hartmut Boesch,et al.  Global Characterization of CO2 Column Retrievals from Shortwave-Infrared Satellite Observations of the Orbiting Carbon Observatory-2 Mission , 2011, Remote. Sens..

[7]  H. Tran,et al.  Spectral shape parameters of pure CO2 transitions near 1.6 µm by tunable diode laser spectroscopy , 2015 .

[8]  S. Tashkun,et al.  CDSD-1000, the high-temperature carbon dioxide spectroscopic databank , 2003 .

[9]  R. Ciuryło,et al.  Quadratic speed dependence of collisional broadening and shifting for atmospheric applications , 2015 .

[10]  V. Malathy Devi,et al.  Spectroscopic challenges for high accuracy retrievals of atmospheric CO2 and the Orbiting Carbon Observatory (OCO) experiment , 2005 .

[11]  Rebecca Castano,et al.  The ACOS CO 2 retrieval algorithm – Part II: Global X CO 2 data characterization , 2012 .

[12]  S. Tashkun,et al.  A room temperature CO2 line list with ab initio computed intensities , 2016, 1601.05334.

[13]  P. Chelin,et al.  Abinitiocalculations of the spectral shapes of CO2isolated lines including non-Voigt effects and comparisons with experiments , 2013 .

[14]  William C. Swann,et al.  Pressure-induced shift and broadening of 1510–1540-nm acetylene wavelength calibration lines , 2000 .

[15]  A. Predoi‐Cross,et al.  Computations of temperature dependences for line shape parameters in the 30012 ← 00001 and 30013 ← 00001 bands of pure CO2 , 2009 .

[16]  V. Malathy Devi,et al.  Line mixing and speed dependence in CO2 at 6348 cm-1: Positions, intensities, and air-and self-broadening derived with constrained multispectrum analysis , 2007 .

[17]  R. R. Gamache,et al.  Einstein A coefficient, integrated band intensity, and population factors: application to the a^1@D , 2001 .

[18]  Masakatsu Nakajima,et al.  Thermal and near infrared sensor for carbon observation Fourier-transform spectrometer on the Greenhouse Gases Observing Satellite for greenhouse gases monitoring. , 2009, Applied optics.

[19]  Robert R. Gamache,et al.  Predicting accurate line shape parameters for CO2 transitions , 2013 .

[20]  Christopher Johnstone,et al.  Near infrared spectroscopy of carbon dioxide. II: 16O13C16O and 16O13C18O line positions , 2004 .

[21]  V. Malathy Devi,et al.  Temperature dependences for air-broadened Lorentz half-width and pressure shift coefficients in the 30013/00001 and 30012/00001 bands of CO 2 near 1600 nm 1 , 2009 .

[22]  L. Rothman,et al.  Extension of the hitran database to non-LTE applications , 1992 .

[23]  Ha Tran,et al.  Influence of line mixing on the retrievals of atmospheric CO 2 from spectra in the 1.6 and 2.1 μm regions , 2009 .

[24]  Rebecca Castano,et al.  Atmospheric validation of high accuracy CO2 absorption coefficients for the OCO-2 mission , 2012 .

[25]  V. M. Devi,et al.  A multispectrum nonlinear least squares fitting technique , 1995 .

[26]  V. Malathy Devi,et al.  Self-broadened widths and shifts of 12C16O2: 4750–7000 cm−1 , 2006 .

[27]  David Crisp,et al.  Precision requirements for space-based XCO2 data , 2007 .

[28]  D. Hurtmans,et al.  Line profile study of transitions in the 30012 ← 00001 and 30013 ← 00001 bands of carbon dioxide perturbed by air , 2007 .

[29]  Jean-Michel Hartmann,et al.  Efficient computation of some speed-dependent isolated line profiles , 2013 .

[30]  Kendra L. Letchworth,et al.  RAPID AND ACCURATE CALCULATION OF THE VOIGT FUNCTION , 2007 .

[31]  V. M. Devi,et al.  A cryogenic Herriott cell vacuum-coupled to a Bruker IFS-125HR , 2014 .

[32]  Charles E. Miller,et al.  Near infrared spectroscopy of carbon dioxide I. 16O12C16O line positions , 2004 .

[33]  J. Hodges,et al.  High-Accuracy CO(2) Line Intensities Determined from Theory and Experiment. , 2015, Physical review letters.

[34]  J. Lamouroux,et al.  CDSD-296, high resolution carbon dioxide spectroscopic databank: Version for atmospheric applications , 2015 .

[35]  V. Malathy Devi,et al.  Line positions and strengths of 16O12C18O, 18O12C18O and 17O12C18O between 2200 and 7000 cm−1 , 2007 .

[36]  D. Hurtmans,et al.  Line shape parameters measurement and computations for self-broadened carbon dioxide transitions in the 30012 ← 00001 and 30013 ← 00001 bands, line mixing, and speed dependence , 2007 .

[37]  David Crisp,et al.  The Orbiting Carbon Observatory (OCO) mission , 2004 .

[38]  G. Toon,et al.  Carbon dioxide column abundances at the Wisconsin Tall Tower site , 2006 .

[39]  M. Marangoni,et al.  Communication: Saturated CO2 absorption near 1.6 μm for kilohertz-accuracy transition frequencies. , 2015, The Journal of chemical physics.

[40]  V. Malathy Devi,et al.  Measurement and computations for temperature dependences of self-broadened carbon dioxide transitions in the 30012←00001 and 30013←00001 bands , 2010 .

[41]  Gang Li,et al.  The HITRAN 2008 molecular spectroscopic database , 2005 .

[42]  L. Rothman,et al.  Direct numerical diagonalization: Wave of the future , 1992 .

[43]  V. Malathy Devi,et al.  Line mixing and speed dependence in CO2 at 6227.9 cm−1: Constrained multispectrum analysis of intensities and line shapes in the 30013 ← 00001 band , 2007 .

[44]  Hartmut Boesch,et al.  Orbiting Carbon Observatory: Inverse method and prospective error analysis , 2008 .

[45]  Daniele Romanini,et al.  High-sensitivity CW-cavity ringdown spectroscopy of 12CO2 near 1.5 μm , 2005 .

[46]  Rebecca Castano,et al.  The ACOS CO 2 retrieval algorithm – Part 1: Description and validation against synthetic observations , 2011 .

[47]  V. M. Devi,et al.  Absolute line intensities in CO2 bands near 4.8 mum. , 1986, Applied optics.

[48]  Charles E. Miller,et al.  NASA Orbiting Carbon Observatory: measuring the column averaged carbon dioxide mole fraction from space , 2008 .

[49]  J. Hodges,et al.  Cavity ring-down spectrometer for high-fidelity molecular absorption measurements , 2015 .

[50]  J. Hartmann,et al.  CO2 isolated line shapes by classical molecular dynamics simulations: influence of the intermolecular potential and comparison with new measurements. , 2014, The Journal of chemical physics.

[51]  J. Hodges,et al.  Absolute 12C16O2 transition frequencies at the kHz-level from 1.6 to 7.8 µm , 2013 .

[52]  V. Malathy Devi,et al.  Air-broadened halfwidth and pressure shift coefficients of 12C16O2 bands: 4750–7000 cm−1 , 2007 .

[53]  Robert R. Gamache,et al.  Semiclassical calculations of half-widths and line shifts for transitions in the 30012←00001 and 30013←00001 bands of CO2. III: Self collisions , 2012 .

[54]  A. G. Maki,et al.  Absolute frequency measurements of the 2-0 band of CO at 2.3 μm; Calibration standard frequencies from high resolution color center laser spectroscopy , 1983 .