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arXiv · 1811.07585

Monitoring the optical turbulence in the surface layer at Dome C, Antarctica, with sonic anemometers

Eric Aristidi·Jean Vernin·Eric Fossat·F. -X. Schmider·Tony Travouillon·Cyprien Pouzenc·Olivier Traullé·Christophe Genthon·Abdelkrim Agabi·Erick Bondoux·Zalpha Challita·Djamel Mékarnia·François Jeanneaux·Guillaume Bouchee
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Abstract

The optical turbulence above Dome C in winter is mainly concentrated in the first tens of meters above the ground. Properties of this so-called surface layer (SL) were investigated during the period 2007-2012 by a set of sonics anemometers placed on a 45 m high tower. We present the results of this long-term monitoring of the refractive index structure constant Cn2 within the SL, and confirm its thickness of 35m. We give statistics of the contribution of the SL to the seeing and coherence time. We also investigate properties of large scale structure functions of the temperature and show evidence of a second inertial zone at kilometric spatial scales.

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Eric Aristidi, Jean Vernin, Eric Fossat, F. -X. Schmider, Tony Travouillon, Cyprien Pouzenc, Olivier Traullé, Christophe Genthon, Abdelkrim Agabi, Erick Bondoux, Zalpha Challita, Djamel Mékarnia, François Jeanneaux, Guillaume Bouchee. 2018-11-19. Monitoring the optical turbulence in the surface layer at Dome C, Antarctica, with sonic anemometers. https://doi.org/10.1093/mnras/stv2273

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