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Simultaneous Measurements of the Fried Parameter r_0 and the Isoplanatic Angle theta_0 using SCIDAR and Adaptive Optics - First Results

A. R. Weiss·S. Hippler·M. E. Kasper·N. J. Wooder·J. C. Quartel
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Abstract

We present first results of a simultaneous atmospheric turbulence measurement campaign at the Calar Alto (Spain) 1.23m and 3.5m telescopes. A SCIDAR instrument and the Calar Alto Adaptive Optics system ALFA were used at the 1.23m and 3.5m telescopes respectively to determine essential turbulence parameters like the Fried parameter r_0, the isoplanatic angle theta_0, and, in the case of SCIDAR, the C_n^2 profile of the atmosphere. Both closed-loop and open-loop data were obtained with ALFA. The desired parameters were then calculated from this. This paper shows a comparison of the results obtained from the two different systems for several times during a period of three nights.

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A. R. Weiss, S. Hippler, M. E. Kasper, N. J. Wooder, J. C. Quartel. 2001-01-26. Simultaneous Measurements of the Fried Parameter r_0 and the Isoplanatic Angle theta_0 using SCIDAR and Adaptive Optics - First Results. https://arxiv.org/abs/astro-ph/0101474

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