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arXiv · 1501.02156

Instrumentation for comparing night sky quality and atmospheric conditions of CTA site candidates

Christian Fruck·Markus Gaug·Jean-Pierre Ernenwein·Dušan Mandát·Thomas Schweizer·Dennis Häfner·Tomasz Bulik·Marek Cieslar·Heide Costantini·Michal Dominik·Jan Ebr·Markus Garczarczyk·Eckart Lorentz·Giovanni Pareschi·Miroslav Pech·Irene Puerto-Giménez·Masahiro Teshima
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Abstract

Many atmospheric and climatic criteria have to be taken into account for the selection of a suitable site for the next generation of imaging air-shower Cherenkov telescopes, the "Cherenkov Telescope Array" CTA. Such data are not available with sufficient precision, thus a comparison of the proposed sites and final decision based on a comprehensive characterization is impossible. Identical cross-calibrated instruments have been developed which allow for precise comparison between sites, the cross-validation of existing data, and the ground-validation of satellite data. The site characterization work package of the CTA consortium opted to construct and deploy 9 copies of an autonomous multi-purpose weather sensor, incorporating an infrared cloud sensor, a newly developed sensor for measuring the light of the night sky, and an All-Sky-Camera, the whole referred to as Autonomous Tool for Measuring Observatory Site COnditions PrEcisely (ATMOSCOPE). We present here the hardware that was combined into the ATMOSCOPE and characterize its performance.

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Christian Fruck, Markus Gaug, Jean-Pierre Ernenwein, Dušan Mandát, Thomas Schweizer, Dennis Häfner, Tomasz Bulik, Marek Cieslar, Heide Costantini, Michal Dominik, Jan Ebr, Markus Garczarczyk, Eckart Lorentz, Giovanni Pareschi, Miroslav Pech, Irene Puerto-Giménez, Masahiro Teshima. 2015-02-27. Instrumentation for comparing night sky quality and atmospheric conditions of CTA site candidates. https://doi.org/10.1088/1748-0221%2F10%2F04%2Fp04012

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