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arXiv · 2505.02122

Aerosol Measurement in B, V, and R Filters using Wide-field Photometry

Shefali Negi·Jan Ebr·Sergey Karpov·Jiří Eliášek
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Abstract

The new method for aerosol measurement using wide-field stellar photometry was originally developed for B-filter data. The dependence of VAOD (vertical aerosol optical depth) on wavelength can be used to understand the physical characteristics of aerosol. The method has been extended for V and R filters using the Gaia stellar photometric catalog as the reference. We calculated the coefficients of the equation describing molecular and aerosol extinction of the atmosphere. For data in a particular filter, they depend on the telescope's location. Light towards shorter wavelengths has higher extinction. The VAOD, calculated in B, V, and R filters does not show monotonous dependence on wavelength, and there is increased dependence on the photometric methods for V and R filters. We studied the possible reasons for this unexpected behavior.

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Shefali Negi, Jan Ebr, Sergey Karpov, Jiří Eliášek. 2025-05-04. Aerosol Measurement in B, V, and R Filters using Wide-field Photometry. https://doi.org/10.1088/1742-6596%2F2985%2F1%2F012011

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