1. 69th Meeting - Champaign-Urbana, Illinois, 2014 TI08 1/13 JPL Progress Report Accurate line intensities for 16 O 12 C 17 O (627) in the 2.1 µm region (the OCO-2 strong band) David Jacquemart 1,2, Keeyoon Sung 3, Linda R. Brown 3, Arlan W. Mantz 4, Mary Ann H. Smith 5 1 UPMC Univ Paris 06, Laboratoire de Dynamique, Interactions et Réactivité, Paris, France. 2 CNRS, UMR 7075, Laboratoire de Dynamique, Interactions et Réactivité, Paris, France. 3 Jet Propulsion Laboratory/California Institute of Technology, Pasadena, CA 4 Dept. of Physics, Astronomy and Geophysics, Connecticut College, New London, CT 5 Science Directorate, NASA Langley Research Center, Hampton, VA

2. 69th Meeting - Champaign-Urbana, Illinois, 2014 TI08 2/13 JPL CO 2 minor isotopologues Intensity measurements and uncertainties  Status of measurement uncertainties (for strong bands)  How to improve OCO[627] line strength measurement uncertainty the limiting factor: Molecular abundance in the sample How to be sure of molecular abundances in our sample? Option#1 – Use manufacturer’s atomic abundances Option#2 – Perform independent sample characterization - WE DID. 1) Obtained a 17 O-enhanced CO 2 sample 2) Characterized the sample by mass spectrometry. SpeciesPosition (cm -1 )Intensity (%)Measurement availableABSCO list OCO[626] 0.0001 < 1 Benner et al. (unpublished) OCO[636] 0.0001~ 1 OCO[628]0.0012 – 3Toth et al.[2008] ~ 5Borkov et al.[2013] OCO[627] 0.001~ 5Lyulin et al. [2012] Borkov et al. [2013] Toth et al. (HITRAN) 10 – 15Karlovets et al.[2013]

3. 69th Meeting - Champaign-Urbana, Illinois, 2014 TI08 3/13 JPL Mass spectrometry: Notations and terms  Atomic isotope ratio The letter, R, is reserved for atomic fractions R13 = [ 13 C]/[ 12 C]; R17 = [ 17 O]/[ 16 O]; R18 = [ 18 O]/[ 16 O]  Depletion factor δ (‰) = (R sample – R std )/R std × 1000 International Standards for C, PDB (Pee Dee Belemnite) For O, V-SMOW (Vienna Standard Mean Ocean Water) e.g.) δ 18 O = 0 for SMOW by definition e.g.) Earth’s tropospheric O 2 shows δ 18 O = + 23.5 ‰.  Construction of normal sample of CO 2 [CO 2 ]= ([ 12 C]+[ 13 C]) × ([ 16 O]+[ 17 O]+[ 18 O]) × ([ 16 O]+[ 17 O]+[ 18 O]) = [626]×(1+R13) × (1+R17+R18) 2  Two sets of mass spec measurement (to correct fractionation effect, measured a reference and a target sample) Reference CO 2 gas: δ 13 C = –10.44 PDB, δ 18 O = +31.22 V-SMOW Target sample bottle: 17 O-enhanced ( 17 O atom > 45%)

4. 69th Meeting - Champaign-Urbana, Illinois, 2014 TI08 4/13 JPL Mass spectrum data analysis: A tomic abundance  (Stable) Isotope-Ratio Mass Spectrometer (IRMS) What are measured quantities?  M values: mole fraction of CO 2 isotopologues by mass/charge M-values factors Components M45/44 = ([636] + [627]) / [626] = R13 + 2×R17 M46/44 = ([628] + [637] + [727]) / [626] = 2×R18 + R17 2 + 2×R13×R17 M47/44 = ([728] + [638] + [737]) / [626] = 2×R17×R18 + R13×R17 2 + 2×R13×R18 M48/44 = ([828] + [738]) / [626] = R18 2 + 2×R13×R17×R18 M49/44 = [838] / [626] = R13×R18 2  Determine atomic abundance Find R to minimize χ 2 = ∑ i {( M i meas - M i cal )/δM i meas } 2 RR Meas (uncalibrated) Corr.Fac, ξ (R True /R Meas ) R Meas. (calibrated) isotopesTotal Atom (%) R121 1[ 12 C]98.94(±0.33) R130.010835 0.989 0300.01 0716[ 13 C] 1.06(±0.33) R161 1 [ 16 O]39.34(±0.55) R171.321183 0.986 159 1.302 897 [ 17 O]51.26(±0.33) R180.245532 0.972 319 0.232 093 [ 18 O] 9.39(±0.49) Note: Agreed to the vendor’s specificatoin: 17 O-enhanced ( 17 O atom > 45%).

5. 69th Meeting - Champaign-Urbana, Illinois, 2014 TI08 5/13 JPL Calculation of Molecular abundances  Gas mixture at equilibrium: Sample purity = 100 % (given) Used statistical law to calculate molecular abundances  Molecular isotopologue abundances Iso#Isotopologues%Abundances $ %(δA/A) & 4[ 12 C 16 O 17 O][627]39.91 (±0.82) 2.1 8[ 12 C 17 O 17 O][727]26.00 (±0.34) 13.1 1[ 12 C 16 O 16 O][626]15.32 (±0.42) 2.7 [ 12 C 17 O 18 O][728] 9.53 (±0.56) 5.9 3[ 12 C 16 O 18 O][628] 7.31 (±0.48) 6.6 7[ 12 C 18 O 18 O][828] 0.87 (±0.09) 10.3 6[ 13 C 16 O 17 O][637] 0.43 (±0.14) 32.6 [ 13 C 17 O 17 O][737] 0.28 (±0.09) 32.1 2[ 13 C 16 O 16 O][636] 0.16 (±0.06) 37.5 0[ 13 C 17 O 18 O][738] 0.10 (±0.04) 40 5[ 13 C 16 O 18 O][638] 0.08 (±0.03) 37.5 9[ 13 C 18 O 18 O][838] 0.01 (±0.01)100 Total CO 2 100% $ Uncertainties in the parenthesis are relative to the total sample. & Uncertainties are relative to the individual isotopologue abundance.

6. 69th Meeting - Champaign-Urbana, Illinois, 2014 TI08 6/13 JPL New FT-IR spectra with Herriot cell Arlan Mantz Bruker 125HR at JPL Herriott cell

7. 69th Meeting - Champaign-Urbana, Illinois, 2014 TI08 7/13 JPL Instrumental set-up and experimental details Interferometer (Bruker IFS-125HR) IR sourceTungsten lamp (50 W) Beam splitterCaF 2 Resolution0.0056 cm -1 (unapodized) Aperture (diameter) 1.3 mm Focal length418 mm Optical filter range Filter#A: 4500 – 6500 cm -1 Filter#B: 5800 – 6800 cm -1 DetectorInSb (LN 2 cooled) FTS pressure< 0.010 hPa Gas absorption cell Herriott cell (Talk: TI07) BodyOFHC copper Base path (m)0.337 Path length (m) 20.941(6) Cell windowCaF 2 (wedged) Vacuum box window CaF 2 (wedged) Pure CO 2 spectrum Run # Opt. Filter rangeTotal sample Pressure (cm -1 )(Torr)(Atm) 03A4500-650096.930.12754 04B5500-680096.940.12755 05B5500-680044.980.05918 06A4500-650044.970.05917 07A4500-650018.590.02446 08B5500-680018.600.02447 09B5500-68009.6200.01266 10A4500-65009.6190.01266 11A4500-65004.9930.00657 12A4500-65002.0870.00275 13A4500-65001.0650.001401 14A4500-65000.50350.0006625 CO 2 and CO mixture spectrum rangeP(CO 2 )P(CO) (cm -1 )(Torr) 15 none2000-8500~ 0.924~ 0.1

8. 69th Meeting - Champaign-Urbana, Illinois, 2014 TI08 8/13 JPL L = 20.941 m P = 0.5 – 98 Torr T = 296 K Resnl = 0.0056 cm -1 This work: 2 µm region Residual H 2 O HCl [626]; [627]; [628]; [727] Sample spectrum capturing various types of CO 2 isotopologues Future work

9. 69th Meeting - Champaign-Urbana, Illinois, 2014 TI08 9/13 JPL Multispectrum fitting - Required a multispectrum fitting procedure - Employed the program by Jacquemart et al. (2002)

10. 69th Meeting - Champaign-Urbana, Illinois, 2014 TI08 10/13 JPL Choice of line-shape profile: Rautian 4634.7736315(87) cm -1 6.5347(62) 10 -24 cm -1 /(molec.cm -2 ) 0.09795(22) cm -1 /atm 4634.7736308(67) 6.5899(49) 10 -24 cm -1 /(molec.cm -2 ) 0.10131(17) cm -1 /atm  Observed 0.85% on the line intensity: 3 % on line half width Voigt Rautian Position: Intensity: Broadening:

11. 69th Meeting - Champaign-Urbana, Illinois, 2014 TI08 11/13 JPL Vibrational transition dipole moment squared |µ 0 | 2 and Herman Wallis factors The average (obs-calc) values of for the line intensities are given in% with 1SD after the ± sign. For |R 0 | 2, A 1 and A 2 the SD comes from the fit of these parameters.

12. 69th Meeting - Champaign-Urbana, Illinois, 2014 TI08 12/13 JPL Summary Table Generation of complete line list - ongoing Band † Number of measurements Spectral range in cm -1 Band intensity ‡ (cm -1 /molecule.cm -2 ) 00021-00001 734604–4677 1.08×10 -21 01121-01101254604–4650 8.98×10 -23 20011-00001825012–5108 8.74×10 -21 20012-00001864884–4975 3.36×10 -20 20013-00001864763–4858 9.69×10 -21 21111-011011165046–5125 9.11×10 -22 21112-01101894884–4962 3.66×10 -21 21113-01101874738–4801 8.52×10 -22 30011-10001185165–5108 2.87×10 -23 30012-10001214893–4944 9.00×10 -23 30012-10002145004–5038 1.85×10 -23 30013-10002224886–4930 1.55×10 -22 30014-10002114742–4791 4.46×10 -23 22211-0220165090–5125 4.96×10 -23 22213-0220134743–4749 6.31×10 -23 ‡ The band intensity has been estimated through the sum of the calculated line intensities at 296K in cm -1 /(molecule.cm -2 ) for pure 16 O 12 C 17 O.

13. 69th Meeting - Champaign-Urbana, Illinois, 2014 TI08 13/13 JPL Thank you for your attention We also thank Chip Miller for providing the 17 O-enriched CO 2 sample, Max Coleman for the mass spec measurements of the CO 2 sample, Tim Crawford for the technical assistance on the data acquisition with a FT-IR. Acknowledgements Research described in this talk was performed at UPMC/CNRS (France), Connecticut College, NASA Langley Research Center and the Jet Propulsion Laboratory, California Institute of Technology, under contracts and cooperative agreements with the National Aeronautics and Space Administration.