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Refractive Index of Humid Air in the Infrared: Model Fits

Richard J. Mathar
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Abstract

The theory of summation of electromagnetic line transitions is used to tabulate the Taylor expansion of the refractive index of humid air over the basic independent parameters (temperature, pressure, humidity, wavelength) in five separate infrared regions from the H to the Q band at a fixed percentage of Carbon Dioxide. These are least-squares fits to raw, highly resolved spectra for a set of temperatures from 10 to 25 C, a set of pressures from 500 to 1023 hPa, and a set of relative humidities from 5 to 60%. These choices reflect the prospective application to characterize ambient air at mountain altitudes of astronomical telescopes.

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Richard J. Mathar. 2007-02-02. Refractive Index of Humid Air in the Infrared: Model Fits. https://doi.org/10.1088/1464-4258/9/5/008

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