Cavity Ringdown Spectroscopy Of Hydrogen In The 784

Cavity Ring-down Spectroscopy Of Hydrogen In The 784 -852 nm Region And Corresponding Line Shape Implementation Into HITRAN Yan Tan (a, b), Jin Wang (a), Cun-Feng Cheng (a), An-Wen Liu (a), Shui-Ming Hu (a), P. Wcislo (b, c), R. V Kochanov (b, d), I. E. Gordon (b), L. S. Rothman (b) (a)Hefei National Laboratory for Physical Sciences at Microscale, University of Science and Technology of China; (b) Atomic and Molecular Physics Division , Harvard-Smithsonian Center for Astrophysics, USA; (c) Institute of Physics, Faculty of Physics, Astronomy and Informatics, Nicolaus Copernicus University in Torun, Poland; (d)Laboratory of Quantum Mechanics of Molecules and Radiative Processes, Tomsk State University, Russia University of Science and Technology of China

Cavity Ring-down Spectroscopy Of Hydrogen H H v Most abundant molecule in universe J v Most fundamental neutral molecule v Unique molecule – line shape study v Homonuclear diatomic molecule 3 o 2 1 0 p o p S Q 784 -852 nm n=3 -0 O 3 o 2 p 1 0 o p

Cavity Ring-down Spectroscopy Of Hydrogen CW Cavity Ring-down System Iout Ring Down ! I =I 0 exp(-t/τ) time Laser OFF ON In Out OFF PD PZT DAQ PD Pump Laser Ring-down Cavity ULE Etalon Trigger AOM

Cavity Ring-down Spectroscopy Of Hydrogen v Ultrahigh sensitivity R Equivalent absorption path length Leff ≈ L/(1 -R), Leff ~102 km v High frequency accuracy Calibrated with atomic lines, <2 MHz In L Out

Cavity Ring-down Spectroscopy Of Hydrogen Good signal-to-noise ratio for accuracy value V=3 0, J=7 5 H 2, Q(1)

Cavity Ring-down Spectroscopy Of Hydrogen Positions and intensities for the transitions of (3 - 0) H 2 band measured by CRDS

Cavity Ring-down Spectroscopy Of Hydrogen Line position and intensity determination : 3 X 10 -4 cm-1 : -1% Calculation from Pachucki et al. , Phys. Rev. A 83, 042510

Corresponding Line Shape Implementation Into HITRAN Experimental data implementation analysis Our work : CRDS spectra (3 -0) CRDS spectra [in Grenoble] (2 -0) non-Voigt OF-CEAS high-pressure Raman spectra (1 -0) profile New HITRAN online http: //hitran. org/ HITRAN Application Programming Interface (HAPI) HTP (Hartmann-Tran profile) quadratic speed dependence + hard-collisions model P. Wcisło, et al. , J Quant Spectrosc Radiat Transf, 177, 75 -91(2016)

Corresponding Line Shape Implementation Into HITRAN 3 -0 S(1) line

Corresponding Line Shape Implementation Into HITRAN The results of the OF-CEAS and the CRDS spectra analysis for the (1 -0), (2 -0) and (3 -0) bands:

Corresponding Line Shape Implementation Into HITRAN From HITRANonline: http: //hitran. org/ New Output Format Parameter Units C|Fortran Format

Corresponding Line Shape Implementation Into HITRAN Profile Function name Parameters Voigt PROFILE_VOIGT GD, G 0, D 0 Speed-dependent Voigt PROFILE_SDVOIGT GD, G 0, G 2, D 0, D 2, Rautian PROFILE_RAUTIAN GD, G 0, D 0, n. VC Speed-dependent Rautian PROFILE_SDRAUTIAN GD, G 0, G 2, D 0, D 2, n. VC Hartmann-Tran PROFILE_HT GD, G 0, G 2, D 0, D 2, n. VC, h Sample spectra by using HAPI to simulate the absorption coefficient of H 2 1 -0 band Presentation by Roman, “ HITRAN APPLICATION PROGRAMMING INTERFACE (HAPI): EXTENDING HITRAN CAPABILITIES” Tuesday, TG 12 : P 1951 R. V. Kochanov, et al. , J Quant Spectrosc Radiat Transf, 177, 15 -30(2016)

Summary and Outlook Have done: • High precision measurement of ro-vibrational transitions of H 2 • These spectroscopy data along with others have been reanalyzed as a test for non-Voigt profile to HITRAN database For experiments: • Calibration with combs : toward sub-ppb (0. 1 MHz) • Thermo-stabilized (1 m. K) sample cell : toward a determination of k. B For HITRANonline • Successfully tested the Hartman-Tran profile : more measurements for other molecules • Keep on updating the database : http: //hitran. org/ • Introducing line-mixing effect: CH 4

Acknowledgements Thanks for the help of our former group members ( Shui-Ming Hu, An-Wen Liu, Jin Wang and many others…). Also thanks for the help of our HITRAN group members (Laurence Rothman, Iouli Gordon, Roman Kochanov …). HITRANonline: http: //hitran. org/ University of Science and Technology of China

Thanks for your attention! University of Science and Technology of China