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Keeyoon Sung

Photo of Keeyoon Sung


4800 Oak Grove Drive
M/S 200-105

Pasadena, CA 91109





Curriculum Vitae:

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Member of:

Laboratory Studies And Atmospheric Observations


  • Ph.D. in Atmospheric Sciences, SUNY at Stony Brook, NY (2003)
  • M.Sc. course completion in Astronomy, Seoul National Univ. Korea (1998)
  • B.Sc. in Astron. & Space Sci., Chungnam Nat'l Univ. Daejon, Korea (1996)
  • B.A. in English Education, Seoul National Univ. Korea (1990)

Professional Experience

  • Research Scientist, Science Division, JPL/Caltech (2010 - present)
  • Caltech post-doc fellow, JPL/Caltech (2007 - 2010)
  • Post-doc fellow, Univ. of Toronto and Univ. of Waterloo (2003 - 2007)

Community Service

  • Guest reviewer to scientific journals (JQSRT, Icarus, JGR, JCP, JMS, Mol. Phys., ApJ, Nature, etc.).
  • NASA SBIR/STTR proposal review (2009 – 2015, 2021, 2022)
  • NASA-ROSES proposal review (2016, 2017, 2019, 2021)
  • NASA Astro 2020 Science White Paper (2019)
  • Museum and Informal Education Alliance (2016 – present)

Research Interests

  1. High Resolution Infrared Spectroscopy on Earth and Planetary (, including characterization of (a) spectroscopic line parameters for atmospheric trace species, (b) cross sections for hydrocarbons and nitriles at cold temperatures, and (c) collisional line mixing effect and collisional induced absorption through laboratory experiment and model calculations.
  2. Precision modeling of telluric absorption features toward Extreme Precision Radial Velocity (EPRV) measurements.
  3. Atmospheric remote sensing of trace gases using a MK-IV (ground-based and air-borne FT-IR)
  4. Mass spectrum analysis for isotopic abundance characterization

Selected Awards

  • Group Award to OCO-2 Algorithm Team (2020)
  • Voyager award for proposal successes and quality research in the planetary science (2018)
  • Group Award to OCO-2 Algorithm Team (2016)
  • Group Achievement Award to Stratosphere Atmospheric Measurement Team (2015)
  • Group Award for OCO-2 Algorithm Development (2014)
  • Group Award to OCO-2 Science Implementation Team (2012)

Selected Publications

H-Index = 28; Publications = 103; Times cited = 8,762

  1. S. C. Egbert, K. Sung, S. C. Coburn, B. J. Drouin, G. B. Rieker. Water-vapor absorption database using dual comb spectroscopy from 300 to 1300 K part I: Pure H2O, 6600 to 7650 cm-1. JQSRT, 318 (2024). 108940.
  2. T. S. Pagano, H. Cho, T. J. Crawford, P. Hansen, D. L. Johnson, Y. Maruyama, B. Monacelli, Sir B. Rafol, A.Soibel, K. Sung, N. Tallarida, M. Schwochert, R.C. Wilson, M. S. Gibson, C. D. Smith, T. U. Kampe, "Thermal vacuum performance testing of the CubeSat Infrared Atmospheric Sounder (CIRAS)," Proc. SPIE 12689, CubeSats, SmallSats, and Hosted Payloads for Remote Sensing VII, 1268906 (5 October 2023); https://doi:10.1117/12.2682477
  3. R. R. Gamache, N. Orphanos, B. Vispoel, K. Sung and G. C. Toon. Measurements of H2O-O2 line shape parameters and the determination of the intermolecular potential for modified complex Robert-Bonamy calculations. MOLECULAR PHYSICS e2281592.
  4. B. Steffens, K. Sung, et al. Pseudoline generation for trans-2-butene in the 7-15 µm region in support of Titan atmosphere study. Journal of Quantitative Spectroscopy & Radiative Transfer 310 (2023) 108730.
  5. A.V. Nikitin, A. Campargue, A.E. Protasevich, M. Rey, K. Sung, Vl.G. Tyuterev. Analysis of experimental spectra of phosphine in the Tetradecad range near 2.3 μm using ab initio calculations. Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy. 302, 122896 (2023).
  6. K. Sung , E. H. Wishnow, B. J. Drouin, L. Manceron, M. Verseils, D. Chris Benner, C. A. Nixon. The rotational spectrum of HD broadened by H 2 at temperatures between 100 –296 K. Journal of Quantitative Spectroscopy & Radiative Transfer 295 (2023) 108412.
  7. Z.-C. Zeng , O. Addington , T. P., R.L. Herman, K. Sung , et al. Remote sensing of atmospheric HDO/H2O in southern California from CLARS-FTS, Quant. Spectrosc. Radiat. Transfer (2022).
  8. B.L. Steffens, C.A. Nixon , K. Sung, P.G. J. Irwin, N.A. Lombardo, E. Pereira. New Constraints on Titan’s Stratospheric n-Butane Abundance. Planetary Science Journal, 3:59 (2022).
  9. X. Huang, K. Sung, G.C. Toon, D.W. Schwenke, T.J. Lee. A collaborative 14NH3 IR spectroscopic analysis at 6000cm-1. Journal of Quantitative Spectroscopy & Radiative Transfer 280 (2022) 108076.
  10. A .A . Rodina, A.V. Nikitin, L. Manceron, X. Thomas, L. Daumont, M. Rey, K. Sung, et al. Improved line list of 12CH4 in the 4100–4300 cm-1 region. Journal of Quantitative Spectroscopy & Radiative Transfer 279 (2022) 108021.
  11. I.E. Gordon, L.S. Rothman, et al. The HITRAN2020 molecular spectroscopic database. J Quant. Spectrosc. Radiat. Transfer 277 (2022) 107949.
  12. N..A. Malarich, D. Yun, K. Sung, S.C. Egbert, S.C. Coburn, B.J. Drouin, G.B. Rieker. Dual frequency comb absorption spectroscopy of CH4 up to 1000 K from 6770-7630 cm-1. JQSRT, Submitted to HITRAN special issue.
  13. Z.C. Zeng, V. Natraj, F. Xu, S. Chen, F.-Y. Gong, T.J. Pongetti, K. Sung, G. Toon, S.P. Sander, Y.L. Yung. GFIT3: A full physics retrieval algorithm for remote sensing of greenhouse gases in the presence of aerosols. Submitted.
  14. H.S.P. Müller, A. Belloche, F. Lewen, B.J. Drouin, K. Sung, R.T. Garrod, K.M. Menten. Toward a global model of the interactions in low-lying states of methyl cyanide: rotational and rovibrational spectroscopy of the 34 = 1 state and tentative interstellar detection of the 34 = 38 = 1 state in Sgr B2(N). Accepted. arXiv:2103.07389
  15. G. C. Toon, J.-F. Blavier, K. Sung, K. Yu. Spectrometric measurements of atmospheric 1 propane (C­3H8). Accepted,
  16. Z.-C. Zeng, O. Addington, T. Pongetti, R. Herman, K. Sung, S. Newman, A. Schneider, T. Borsdorff, Y.L. Yung, S.P. Sander. Measurements of atmospheric HDO/H2O in southern California from 1 CLARS-FTS. JGR-Atmosphere, Submitted.
  17. K. Sung, B. Steffens, G.C. Toon, D.J. Nemchick. Pseudoline parameters to represent n-butane (nC4H10) cross-sections measured in the 7–15 μm region for the Titan atmosphere. JQSRT, 251 (2020) 107011.
  18. K. Sung, V.M. Devi, D.C. Benner, B.J. Drouin, T.J. Crawford, A.W. Mantz, M.H. Smith. H2-pressure broadening and frequency shifts of methane in the v2+v3 band measured in the temperature range between 80 and 370 K. JQSRT, 255 (2020) 107264.
  19. K.D. Doney, V. Kofman, G.L. Villanueva, K. Sung. A new model of monodeuterated ethane (C2H5D) spectrum: Enabling sensitive constraints on the D/H in ethane emission in comets. JQSRT, 255 (2020) 107225.
  20. A.V. Nikitin, A .A . Rodina, X. Thomas, L. Manceron, L. Daumont, M. Rey, K. Sung, et al. Line list of 12CH4 in the 4300–4600 cm−1 region. JQSRT, 253 (2020) 107061.
  21. V.H. Payne, B.J. Drouin, F. Oyafuso, L. Kuai, B.M. Fisher, K. Sung, et al. Absorption coefficient (ABSCO) tables for the Orbiting Carbon Observatories: Version 5.1. JQSRT, 255 (2020) 107217.
  22. C. Bao, Z. Yuan, H. Wang, L. Wu, B. Shen, K. Sung, S. Leifer, Q. Lin, K. Vahala. Interleaved difference-frequency generation for microcomb spectral densification in the mid-infrared. Optica, 7, 309-315, Apr 2020.
  23. K. Sung, E.H. Wishnow, T.J. Crawford, et al. FTS measurements of O 2 collision-induced absorption in the 565-700 nm region using a high pressure gas absorption cell, J.Quant. Spectrosc. Radiat. Transfer, 235, 232-243 (2019).
  24. T. Karman, I.E. Gordon, .., K. Sung, et al. Update of the HITRAN collision-induced absorption section, J.Quant. Spectrosc. Radiat. Transfer, 328, 160-175 (2019)
  25. N. Lombardo, C.A. Nixon, R. Achterberg, ..,K. Sung, et al. Spatial and seasonal variations in C3Hx hydrocarbon abundance in Titan's stratosphere from Cassini CIRS observations. Icarus 317: 454-469 (2019).
  26. A. Nikitin, X. Thomas, L. Daumont, ..,K. Sung, et al. Assignment and modelling of (CH4)-C-12 spectra in the 5550-5695, 5718-5725 and 5792-5814 cm(-1) regions. J.Quant. Spectrosc. Radiat. Transfer, 219: 323-332 (2018).
  27. K. Sung, G.C. Toon, B.J. Drouin, et al. FT-IR measurements of cold propene (C3H6) cross-sections at temperatures between 150 and 299 K. J.Quant. Spectrosc. Radiat. Transfer, 213, 119-132 (2018).
  28. E. Starikova, K. Sung, A.V. Nikitin, et al. The 13CH4 in the lower part of the Tetradecad at 80 K: Assignment and modeling. J.Quant. Spectrosc. Radiat. Transfer, 206, 306-312 (2018).
  29. D. Jacquemart, K. Sung, M. Coleman, et al. Measurements and modeling of (OCO)-O-16-C-12-O-17 spectroscopic parameters at 2 mu. J.Quant. Spectrosc. Radiat. Transfer, 203: 249-264, (2017). doi: 10.1016/j.jqsrt.2017.03.002
  30. I.E. Gordon, L.S. Rothman, et al. The HITRAN 2016 molecular spectroscopic database. J.Quant. Spectrosc. Radiat. Transfer, 203, 3 - 69 (2017).
  31. A.V. Nikitin, X. Thomas, Daumont L, Rey M, K. Sung, G.C. Toon, Smith MAH, et al. Measurements and modeling of long-path 12 CH4 spectra in the 5300-5550 cm−1 region. J.Quant. Spectrosc. Radiat. Transfer, 202, 255-264 (2017).
  32. V.M. Devi, D.C. D.C. Benner, K. Sung, et al. Line parameters for CO2 broadening in the v3 band of HD16O. J.Quant. Spectrosc. Radiat. Transfer, 203, 158-174 (2017).
  33. G.C. Toon, J.-F. Blavier, K. Sung, et al. HITRAN spectroscopy evaluation using solar occultation FTIR spectra. J.Quant. Spectrosc. Radiat. Transfer, 182, 324 - 336 (2016).
  34. K. Sung, S. Yu, J. Pearson, et al. Far-infrared 14NH3 line positions and intensities measured with a FT-IR and AILES beamline, Synchrotron SOLEIL. J. MOL. SPECTROSC., 327, 1 - 20 (2016).
  35. N. Jacquinet-Husson, R. Armante, N.A. Scott, et al...K. Sung, et al. The 2015 edition of the GEISA spectroscopic database. J. MOL. SPECTROSC., 327, 31 - 72 (2016).
  36. V. M. Devi, D. C. Benner, K. Sung, L.R. Brown, et al. Line parameters including temperature dependences of air- and self-broadened line shapes of 12C16O2: 1.6 μm region. J.Quant. Spectrosc. Radiat. Transfer, 177, 117 - 144 (2016).
  37. D.C. Benner, V.M. Devi, K. Sung, L.R. Brown, et al. Line parameters including temperature dependences of air- and self-broadened line shapes of 12 C16O2: 2.06 μm region. J. MOL. SPECTROSC., 326, 21 - 47 (2016).
  38. L. R. Brown, A.V. Nikitin, K. Sung, M. Rey, S.A. Tashkun, et al. Measurements and modeling of cold 13CH4 spectra in the 3750-4700 cm-1 region. J.Quant. Spectrosc. Radiat. Transfer, 174, 88 - 100 (2016).
  39. K. Sung, G.C. Toon, T.J. Crawford. N2- and (H2+He)-broadened cross sections of benzene (C6H6) in the 7 - 15 μm region for the Titan and jovian atmospheres. Icarus, 271, 438 0 452 (2016). Erratum. Icarus, 281, 476 - 476 (2017).
  40. A.M. Daly, B.J. Drouin, J.C. Pearson, P. Groner, K. Sung, L.R. Brown, et al. The v7 band of CH3CH2D from 770-850 cm-1. J. Mol. Spectrosc., 316, 1 - 10 (2015).
  41. N. Moazzen-Ahmadi, J.N. Oliaee, I. Ozier, E.H. Wishnow, K. Sung, et al. An intensity study of the torsional bands of ethane at 35 μm. J.Quant. Spectrosc. Radiat. Transfer, 151, 123 - 132 (2015).
  42. A.W. Mantz, K Sung, LR Brown, Crawford TJ, MAH Smith, VM Devi, DC Benner. A cryogenic Herriott cell vacuum-coupled to a Bruker IFS-125HR.J. Mol. Spectrosc. 304, 12 - 14 (2014).
  43. C.A. Nixon, D.E. Jennings, B. Bézard, S. Vinatier, N.A. Teanby, K. Sung, et al. Detection of propene in Titan's atmosphere, Astrophys. J. Lett. 776, L14 (2013).
  44. K. Sung, G.C. Toon, A.W. Mantz, M.A.H. Smith. FT-IR measurements of cold C3H8 cross sections at 7 - 15 μm for Titan atmosphere. Icarus, 226, 1499 - 1513 (2013).
  45. L.R. Brown, K. Sung, D.C. Benner, V.M. Devi, et al,., Methane line parameters in the HITRAN 2012 database, J. Quant. Spectrosc. Radiat. Transfer 130, 201 - 219 (2013).
  46. K. Sung, L.R. Brown, X. Huang, D.M. Schwenke, S.L. Coy, K.K. Lehmann. Extended line positions, intensities, empirical lower state energies and quantum assignments of NH3 from 6300 to 7000 cm-1. J. Quant. Spectrosc. Radiat. Transfer, 113, 1066 - 1183 (2012)
  47. C.S. Brauer, K. Sung, J.P. Pearson, L.R. Brown, and L.H. Xu. Empirical line intensities of methanol in the 300 - 500 cm-1 region. J. Mol. Spectrosc., 113, 128-139 (2012).
  48. K. Sung, A.W. Mantz, L.R. Brown, M.A.H. Smith, T.J. Crawford, V.M. Devi, and D.C. Benner. Cryogenic absorption cells operating inside a Bruker IFS-125HR: first results for 13CH4 at 7 μm. J. Mol. Spectrosc. 262, 122- 134 (2010).
  49. R.A. Toth, K. Sung, L.R. Brown, and T.J. Crawford. Line positions and strengths of 41 bands including 10 OCS isotopologues in the 3850 - 4200 cm-1 region. J. Quant. Spectrosc. Radiat. Transfer, 111, 1193-1208 (2010).
  50. K. Sung, L.R. Brown, R.A. Toth, and T.J. Crawford, FT-IR measurements of H2O-broadened half-widths of CO2 at 4.3 μm. Canad. J. Phys. 87, 469 -484 (2009).
  51. K. Sung, R.A. Toth, L.R. Brown, and T.J. Crawford. Line strength measurements of carbonyl sulfide (16O12C32S) in the 2v3, v1+2v2+v3, and 4v2+v3 bands. J. Quant. Spectrosc. Radiat. Transfer, 110, 2082 - 2101 (2009).
  52. D. Fu, K. Sung, C.D. Boone, K.A. Walker, and P.F. Bernath. Ground-based solar absorption studies for the carbon cycle science by Fourier transform spectroscopy (CC-FTS) mission. J. Quant. Spectrosc. Radiat. Transfer, 109, 2219 - 2243 (2008).
  53. K. Sung, R. Skelton, K.A. Walker, C.D. Boone, D. Fu, and P.F. Bernath. N2O and O3 Arctic Column Amounts from PARIS-IR Observations: Retrievals, Characterization and Error Analysis. J. Quant. Spectrosc. Radiat. Transfer, 107, 385 - 406 (2007).
  54. K. Sung and P. Varanasi. CO2-broadened half-widths and CO2-induced line shifts of 12C16O relevant to the atmospheric spectra of Venus and Mars. J. Quant. Spectrosc. Radiat. Transfer, 91, 319 - 332 (2005).
  55. K. Sung and P. Varanasi., Hydrogen-broadened half-widths and hydrogen-induced line shifts of 12C16O relevant to the Jovian atmospheric spectra. J. Quant. Spectrosc. Radiat. Transfer, 85, 165 - 182 (2004).
  56. K. Sung and P. Varanasi. Intensities, collision-broadened half-widths, and collision-induced line shifts in the second overtone band of 12C16O. J. Quant. Spectrosc. Radiat. Transfer, 83, 445 - 458 (2004).
  57. V. Nemtchinov, K. Sung, and P. Varanasi. Measurements of line intensities and half-widths in the 10 μm bands of 14NH3. J. Quant. Spectrosc. Radiat. Transfer, 83, 243 - 265 (2004).