Vol. 34, issue 12, article # 2

Rodimova O. B. On the role of  the continuum absorption definition in the case of the H2O–N2 absorption. // Optika Atmosfery i Okeana. 2021. V. 34. No. 12. P. . DOI: 10.15372/AOO20211202 [in Russian].
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Water vapor continuum absorption in the H2O–N2 mixture is examined on the basis of the CKD model and using the line shape with parameters found from fitting the calculated absorption coefficients to the CRDS data in the 4000–5100 cm-1 window. Differences of these two definitions are analyzed as applied to the IR region. It is shown that the CKD continuum includes the absorption due to excess of the line contour over the Lorentzian one at distances less than 10 cm-1 from the line centers. The possibility is examined of extracting the absorption by additional objects (like water dimers) when calculating the Н2О–N2 continuum absorption on the basis of the ATLW approach.


IR water vapor spectrum, continuum absorption, nitrogen broadening, continuum absorption definition


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