Nascent O2 (a 1Δg, v = 0, 1) rotational distributions from the photodissociation of jet-cooled O3 in the Hartley band

2018 ◽  
Vol 149 (13) ◽  
pp. 134309 ◽  
Author(s):  
Michelle L. Warter ◽  
Carolyn E. Gunthardt ◽  
Wei Wei ◽  
George C. McBane ◽  
Simon W. North
Keyword(s):  
Hartley Band

Formation of O(3Pj) photofragments from the Hartley band photodissociation of ozone at 226 nm

1990 ◽  
Vol 93 (5) ◽  
pp. 3289-3294 ◽  
Author(s):  
Tohru Kinugawa ◽  
Tetsuya Sato ◽  
Tatsuo Arikawa ◽  
Yutaka Matsumi ◽  
Masahiro Kawasaki
Keyword(s):  
Hartley Band

PHOTODISSOCIATION OF OZONE IN THE HARTLEY BAND: FRAGMENT ROTATIONAL QUANTUM STATE DISTRIBUTIONS

2004 ◽  
Vol 03 (03) ◽  
pp. 443-449 ◽  
Author(s):  
MEI-YU ZHAO ◽  
KE-LI HAN ◽  
GUO-ZHONG HE ◽  
JOHN Z. H. ZHANG
Keyword(s):  
Angular Momentum ◽  
Potential Energy ◽  
Wave Packet ◽  
Total Angular Momentum ◽  
Energy Surface ◽  
Potential Surface ◽  
Rotational State ◽  
Time Dependent ◽  
Correct Treatment ◽  
Hartley Band

In this paper, we have calculated the rotational state distributions following the photodissociation of ozone in the Hartley band with total angular momentum J'=1. The calculated results are obtained by using time-dependent wave packet calculations on the Sheppard–Walker potential energy surface (PES). It is found that the physically more correct treatment with J'=1 semi-quantitatively reproduces the rotational state distributions of the CARS. Compared with the previous theoretical works, which had taken J=0 on both the ground and excited potential surface, J'=1 treatment makes the rotational distributions of the fragment closer to the experimental ones.

scholarly journals Sensitivity studies of the recent new data on O(<sup>1</sup><i>D</i>) quantum yields in O<sub>3</sub> Hartley band photolysis in the stratosphere

2003 ◽  
Vol 3 (3) ◽  
pp. 2331-2352 ◽  
Author(s):  
N. Taniguchi ◽  
S. Hayashida ◽  
K. Takahashi ◽  
Y. Matsumi
Keyword(s):  
Atmospheric Chemistry ◽  
Atmospheric Model ◽  
Quantum Yields ◽  
Oh Radicals ◽  
One Dimensional ◽  
Near Ultraviolet ◽  
Steady State Model ◽  
Sensitivity Studies ◽  
Hartley Band ◽  
Excited Oxygen

Abstract. The production yields of excited oxygen O(1D) atoms from the near ultraviolet O3 photolysis are essential quantities for atmospheric chemistry calculations because of its importance as major sources of hydroxyl (OH) radicals and nitric oxide (NO). Recently, new O(1D) quantum yields from O3 photolysis between 230 and 305 nm in the Hartley band region were reported, which are almost independent of the photolysis wavelength (0.88-0.93) and smaller than NASA/JPL-2000 recommendation (0.95 between 240 and 300 nm). In order to assess consequences of the new data of O(1D) quantum yields on the stratospheric chemistry, the changes in stratospheric chemical partitioning and O3 concentration are examined using a one-dimensional atmospheric model. Our steady state model simulations for mid-latitude in March indicate that the smaller O(1D) quantum yields result in increases of stratospheric O3 (up to ~2% in the upper stratosphere), which are attributed to the changes in HOx, NOx, and ClOx abundance and their catalyzed O3 loss rates.

scholarly journals Linearization of the effect of slit function changes for improving Ozone Monitoring Instrument ozone profile retrievals

2019 ◽  
Vol 12 (7) ◽  
pp. 3777-3788 ◽  
Author(s):  
Juseon Bak ◽  
Xiong Liu ◽  
Kang Sun ◽  
Kelly Chance ◽  
Jae-Hwan Kim
Keyword(s):  
Cross Sections ◽  
Shape Factor ◽  
Optimal Estimation ◽  
Ozone Monitoring Instrument ◽  
Thermally Induced ◽  
Monitoring Instrument ◽  
Spectral Fitting ◽  
Ozone Profile ◽  
Ozone Monitoring ◽  
Hartley Band

Abstract. We introduce a method that accounts for errors caused by the slit function in an optimal-estimation-based spectral fitting process to improve ozone profile retrievals from the Ozone Monitoring Instrument (OMI) ultraviolet measurements (270–330 nm). Previously, a slit function was parameterized as a standard Gaussian by fitting the full width at half maximum (FWHM) of the slit function from climatological OMI solar irradiances. This cannot account for the temporal variation in slit function in irradiance, the intra-orbit changes due to thermally induced change and scene inhomogeneity, and potential differences in the slit functions of irradiance and radiance measurements. As a result, radiance simulation errors may be induced due to convolving reference spectra with incorrect slit functions. To better represent the shape of the slit functions, we implement a more generic super Gaussian slit function with two free parameters (slit width and shape factor); it becomes standard Gaussian when the shape factor is fixed to be 2. The effects of errors in slit function parameters on radiance spectra, referred to as pseudo absorbers (PAs), are linearized by convolving high-resolution cross sections or simulated radiances with the partial derivatives of the slit function with respect to the slit parameters. The PAs are included in the spectral fitting scaled by fitting coefficients that are iteratively adjusted as elements of the state vector along with ozone and other fitting parameters. The fitting coefficients vary with cross-track and along-track pixels and show sensitivity to heterogeneous scenes. The PA spectrum is quite similar in the Hartley band below 310 nm for both standard and super Gaussians, but is more distinctly structured in the Huggins band above 310 nm with the use of super Gaussian slit functions. Finally, we demonstrate that some spikes of fitting residuals are slightly smoothed by accounting for the slit function errors. Comparisons with ozonesondes demonstrate noticeable improvements when using PAs for both standard and super Gaussians, especially for reducing the systematic biases in the tropics and midlatitudes (mean biases of tropospheric column ozone reduced from -1.4∼0.7 to 0.0∼0.4 DU) and reducing the standard deviations of tropospheric ozone column differences at high latitudes (by 1 DU for the super Gaussian). Including PAs also makes the retrievals consistent between standard and super Gaussians. This study corroborates the slit function differences between radiance and irradiance, demonstrating that it is important to account for such differences in the ozone profile retrievals.

The collisional quenching of electronically excited oxygen atoms, O(21D2), by the gases NH3, H2O2, C2H6, C3H8, and C(CH3)4, using time-resolved attenuation of atomic resonance radiation

1976 ◽  
Vol 54 (11) ◽  
pp. 1765-1770 ◽  
Author(s):  
I. S. Fletcher ◽  
D. Husain
Keyword(s):  
Resonance Radiation ◽  
Recent Measurement ◽  
Absolute Rate ◽  
Collisional Quenching ◽  
Time Resolved ◽  
Excited Atoms ◽  
Electronically Excited ◽  
Hartley Band ◽  
Excited Oxygen ◽  
Oxygen Atoms

A kinetic study of electronically excited oxygen atoms, O(21D2), is presented. These optically metastable species were generated by repetitive pulsed irradiation in the Hartley-band continuum and monitored photoelectrically in absorption by time-resolved attenuation of resonance radiation at λ = 115.2 nm (O(31D20)←O(21D2). Absolute rate constants for the collisional quenching of O(21D2) are reported for the gases NH3, H2O2, C2H6 C3H8, and C(CH3)4. These are found to be respectively (in units of 10−10 cm3 molecule−1 S−1 at 300 K), 6.3 ± 0.7, 5.2 ± 0.6, 7.3 ± 0.8, 9.5 ± 1.0, and 12.3 ± 1.3. With the exception of a recent measurement for NH3• these data represent the first absolute measurements for these quenching gases. Further, a general comparison is made between absolute rate measurements using this technique and recent work by Schiff and co-workers using time-resolved emission at λ = 630 nm (O(21D2) → O(23P2)) in order to monitor the excited atoms.

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