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Actinic spectrum of N 2 O 5 (i.e. the product of σ N 2 O 5 (λ, T ) (at 230 K) and modelled actinic fluxes) for an overhead ozone column of 283 Dobson units, and different SZAs at 30.5 km.
Source publication
The absorption cross section of N2O5, σN2O5(λ, T), which is known from laboratory measurements with the uncertainty of a factor of 2 (Table 4-2 in (Jet Propulsion Laboratory) JPL-2011; the spread in laboratory data, however, points to an uncertainty in the range of 25 to 30%, Sander et al., 2011), was investigated by balloon-borne observations of t...
Contexts in source publication
Context 1
... σ N 2 O 5 (λ, T ) decreases from the extreme UV-C (λ = 200 nm) to the visible spectral range (λ = 400 nm) over 8 to 9 orders of magnitude 15 ( Fig. 2). On the other hand the actinic flux F (λ) strongly increases with wavelength resulting in two distinct maxima of the actinic spectrum in the mid-and upper stratosphere (i.e. in the UV-C and UV-B) (Fig. 3), of which the shape depends on the solar zenith angle (SZA). The short wavelength maximum of the actinic spectrum is located around λ = 220 nm and the long wavelength maximum between λ = 280 and 320 ...
Context 2
... measured quantum yield for the NO 3 production is close to unity. The combined uncertainties of the absorption cross-section and quantum yield cause σ N 2 O 5 to be uncertain by a factor of 2. Figure 3 displays the actinic spectrum relevant for the photolysis of N 2 O 5 at stratospheric conditions. It shows that two distinct wavelength regions are important for the photolysis of N 2 O 5 . ...
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Citations
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We report on a novel
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research missions. Here we report on the relevant instrumental details and
the novel scaling method used to infer the mixing ratios of UV/vis absorbing
trace gases from their absorption measured in limb geometry. The
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