Absorption Cross Sections of O2(a1Δg) and O2(X3Σg−) in the Region from 1087 to 1700 Å

1975 ◽  
Vol 53 (19) ◽  
pp. 1845-1852 ◽  
Author(s):  
S. Ogawa ◽  
M. Ogawa
Keyword(s):  
Metastable State ◽  
Cross Sections ◽  
Ground State ◽  
Experimental Error ◽  
Wavelength Region ◽  
Absorption Cross ◽  
Band Structures ◽  
The Cross

An attempt has been made to measure the absorption cross sections of O2 in the metastable state a1Δg from 1087 to 1700 Å. The absorption is measurable (σa ≥ 3 × 10−19 cm2) from around 1500 Å towards shorter wavelengths. Many band structures overlaying various continua have been seen. Absorption cross sections of O2 in the ground state X3Σg− also have been measured in the same wavelength region and our results agree with previously published values within experimental error. The cross sections of O2(a1Δg) are generally larger than those of O2(X3Σg−) below 1290 Å except at the wavelengths of a few strong bands of O2(X3Σg−).

scholarly journals The MPI-Mainz UV/VIS Spectral Atlas of Gaseous Molecules of Atmospheric Interest

2013 ◽  
Vol 5 (2) ◽  
pp. 365-373 ◽  
Author(s):  
H. Keller-Rudek ◽  
G. K. Moortgat ◽  
R. Sander ◽  
R. Sörensen
Keyword(s):  
Cross Sections ◽  
Wavelength Region ◽  
Quantum Yields ◽  
The Internet ◽  
Web Pages ◽  
Data Sets ◽  
Absorption Cross ◽  
Large Collection ◽  
Data Files ◽  
The Web

Abstract. We present the MPI-Mainz UV/VIS Spectral Atlas of Gaseous Molecules, which is a large collection of absorption cross sections and quantum yields in the ultraviolet and visible (UV/VIS) wavelength region for gaseous molecules and radicals primarily of atmospheric interest. The data files contain results of individual measurements, covering research of almost a whole century. To compare and visualize the data sets, multicoloured graphical representations have been created. The MPI-Mainz UV/VIS Spectral Atlas is available on the Internet at http://www.uv-vis-spectral-atlas-mainz.org. It now appears with improved browse and search options, based on new database software. In addition to the Web pages, which are continuously updated, a frozen version of the data is available under the doi:10.5281/zenodo.6951.

scholarly journals Cross Section Ionization By Electron Impact Of Helium Like Ions

2021 ◽  
Author(s):  
Manel Hariz Belgacem ◽  
Elhabib Guedda ◽  
Haikel Jelassi
Keyword(s):  
Electron Impact ◽  
Cross Section ◽  
Cross Sections ◽  
Ground State ◽  
The Cross ◽  
State 1 ◽  
Unstable States ◽  
Good Agreement

<sub></sub> In this paper we present our calculation of the cross section ionization by electron impact of C V, N VI and O VII. Using the Flexible Atomic Code (FAC), we obtain the cross sections for the ionization of these ions from the ground state 1<sup>1</sup>S, and from the unstable states 2<sup>1</sup>S and 2<sup>3</sup>S. Our results are in good agreement with those based on the Coulomb Born (CB) approximation and the available measurements.

scholarly journals Radiative properties of coated black carbon aggregates: numerical simulations and radiative forcing estimates

2021 ◽  
Author(s):  
Baseerat Romshoo ◽  
Thomas Müller ◽  
Sascha Pfeifer ◽  
Jorge Saturno ◽  
Andreas Nowak ◽  
...  
Keyword(s):  
Black Carbon ◽  
Cross Section ◽  
Cross Sections ◽  
Asymmetry Parameter ◽  
Radiative Forcing ◽  
Single Scattering ◽  
Radiative Properties ◽  
Absorption Cross ◽  
Parametrization Scheme ◽  
The Cross

Abstract. The formation of black carbon fractal aggregates (BCFAs) from combustion and subsequent aging involves several stages resulting in modifications of particle size, morphology, and composition over time. To understand and quantify how each of these modifications influences the BC radiative forcing, the radiative properties of BCFAs are modelled. Owing to the high computational time involved in numerical modelling, there are some gaps in terms of data coverage and knowledge regarding how radiative properties of coated BCFAs vary over the range of different factors (size, shape, and composition). This investigation bridged those gaps by following a state-of-the-art description scheme of BCFAs based on morphology, composition, and wavelength. The BCFAs radiative properties were investigated as a function of the radius of the primary particle (ao), fractal dimension (Df), fraction of organics (forganics), wavelength (λ), and mobility diameter (Dmob). The radiative properties are calculated using the multiple sphere T-matrix (MSTM) method. Amongst size, morphology, and composition, all the radiative properties showed the highest variability with changing size. The cross-sections varied from 0.0001 μm2 to 0.1 μm2 for BCFA Dmob ranging from 24 nm to 810 nm. After size or Dmob, the absorption cross-section (Cabs) and BC mass absorption cross-section (MACBC) showed the highest sensitivity towards composition or forganics, whereas the asymmetry parameter (g) showed higher dependence on morphology, which is represented by Df. The Ångstrom absorption exponent varied from 1.06 up to 3.6 and increases with the fraction of organics (forganics). The values of the absorption enhancement factor (Eλ) were found between 1.01 and 3.28 in the visible spectrum. The Eλ was derived from Mie calculations for coated volume equivalent spheres, and from MSTM for coated BCFAs. Mie calculated enhancement factors were found to be larger by a factor of 1.1 to 1.5 than their corresponding values calculated from the MSTM method. It is shown that radiative forcings are highly sensitive towards modifications in morphology and composition. The black carbon radiative forcing ΔFTOA (Wm−2) decreases up to 61 % as the BCFA becomes more compact in morphology. Whereas, there is a decrease of > 50 % in ΔFTOA as the organic content of the particle increase up to 90 %. Based on our results, which showed a significant effect of coating and morphology on the BC radiative properties, a parametrization scheme for radiative properties of BC fractal aggregates was developed, which is applicable for modelling, ambient, and laboratory-based BC studies. The parameterization scheme for the cross-sections (extinction, absorption, and scattering), single scattering albedo (SSA), and asymmetry parameter (g) of pure and coated BCFAs as a function of Dmob were derived from tabulated results of the MSTM method. Spanning over an extensive parameter space, the developed parametrization scheme showed promisingly high accuracy up to 98 % for the cross-sections, 97 % for single scattering albedos (SSA), and 82 % for asymmetry parameter (g).

Improved absorption cross-sections of oxygen in the wavelength region 205–240 nm of the Herzberg continuum

1988 ◽  
Vol 36 (12) ◽  
pp. 1469-1475 ◽  
Author(s):  
K. Yoshino ◽  
A.S.-C. Cheung ◽  
J.R. Esmond ◽  
W.H. Parkinson ◽  
D.E. Freeman ◽  
...  
Keyword(s):  
Cross Sections ◽  
Wavelength Region ◽  
Absorption Cross ◽  
Herzberg Continuum

Absorption cross-sections in the vacuum ultra-violet - II. The Schumann-Runge bands of oxygen (2000 to 1750Å)

1954 ◽  
Vol 226 (1167) ◽  
pp. 509-521 ◽  
Keyword(s):  
Oscillator Strength ◽  
Cross Sections ◽  
Ultra Violet ◽  
Oscillator Strengths ◽  
Dissociation Limit ◽  
Absorption Cross ◽  
The Cross ◽  
Vibrational Transitions ◽  
Vacuum Ultra Violet ◽  
The Continuum

Absorption cross-sections for oxygen in the region 2000 to 1750 Å, corresponding to the process O 2 X 3 Σ - g + hv → O 2 B 3 Σ - u have been measured. The oscillator strengths for the vibrational transitions have been calculated from these results. The total oscillator strength (including the continuum) is found to be 0·259. The cross-sections for intermolecular collisions causing deactivation of the upper state are found and analyzed. The (0-19) and (0-20) members of the system are observed, and the dissociation limit found to be 57140 ± 20 K .

Absolute determination of the cross sections of ozone in the wavelength region 339-355 nm at temperatures 220-293 K

1989 ◽  
Vol 94 (D6) ◽  
pp. 8485-8490 ◽  
Author(s):  
Marco Cacciani ◽  
Alcide di Sarra ◽  
Giorgio Fiocco ◽  
Antonella Amoruso
Keyword(s):  
Cross Sections ◽  
Wavelength Region ◽  
Absolute Determination ◽  
The Cross

scholarly journals Panchromatic light funneling through the synergy in hexabenzocoronene–(metallo)porphyrin–fullerene assemblies to realize the separation of charges

2020 ◽  
Vol 11 (27) ◽  
pp. 7123-7132 ◽  
Author(s):  
Maximilian Wolf ◽  
Dominik Lungerich ◽  
Stefan Bauroth ◽  
Maximilian Popp ◽  
Benedikt Platzer ◽  
...  
Keyword(s):  
Cross Sections ◽  
Ground State ◽  
Solar Spectrum ◽  
Strong Absorption ◽  
Absorption Cross ◽  
Porphyrin Dimer

Here, we present a novel butadiyne-linked HBC-ethynyl-porphyrin dimer, which exhibits in the ground state strong absorption cross sections throughout the UV and visible ranges of the solar spectrum.

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