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arXiv · 1402.4739

Determining Atmospheric Aerosol Content With An Infra-red Radiometer

M. K. Daniel·Y. T. E. Lo·P. M. Chadwick
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Abstract

The atmospheric attenuation of Cherenkov photons is dominated by two processes: Rayleigh scattering from the molecular component and Mie scattering from the aerosol component. Aerosols are expected to contribute up to 30 Wm$^{-2}$ to the emission profile of the atmosphere, equivalent to a difference of ~20C to the clear sky brightness temperature under normal conditions. Here we investigate the aerosol contribution of the measured sky brightness temperature at the H.E.S.S. site; compare it to effective changes in the telescope trigger rates; and discuss how it can be used to provide an assessment of sky clarity that is unambiguously free of telescope systematics.

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M. K. Daniel, Y. T. E. Lo, P. M. Chadwick. 2014-02-19. Determining Atmospheric Aerosol Content With An Infra-red Radiometer. https://arxiv.org/abs/1402.4739

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