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arXiv · 0706.1710

New method for atmospheric calibration at the Pierre Auger Observatory using FRAM, a robotic astronomical telescope

Abstract

FRAM - F/(Ph)otometric Robotic Atmospheric Monitor is the latest addition to the atmospheric monitoring instruments of the Pierre Auger Observatory. An optical telescope equipped with CCD camera and photometer, it automatically observes a set of selected standard stars and a calibrated terrestrial source. Primarily, the wavelength dependence of the attenuation is derived and the comparison between its vertical values (for stars) and horizontal values (for the terrestrial source) is made. Further, the integral vertical aerosol optical depth can be obtained. A secondary program of the instrument, the detection of optical counterparts of gamma-ray bursts, has already proven successful. The hardware setup, software system, data taking procedures, and first analysis results are described in this paper.

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Segev BenZvi, Martina Bohacova, Brian Connolly, Jiri Grygar, Miroslav Hrabovsky, Tatiana Karova, Dusan Mandat, Petr Necesal, Dalibor Nosek, Libor Nozka, Miroslav Palatka, Miroslav Pech, Michael Prouza, Jan Ridky, Petr Schovanek, Radomir Smida, Petr Travnicek, Primo Vitale, Stefan Westerhoff. 2007-06-12. New method for atmospheric calibration at the Pierre Auger Observatory using FRAM, a robotic astronomical telescope. https://arxiv.org/abs/0706.1710

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