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arXiv · 1207.4581

Accurate measurement of Cn2 profile with Shack-Hartmann data

Juliette Voyez·Clélia Robert·Vincent Michau·Jean Marc Conan·Thierry Fusco
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Abstract

The precise reconstruction of the turbulent volume is a key point in the development of new-generation Adaptive Optics systems. We propose a new Cn2 profilometry method named CO-SLIDAR (COupled Slope and scIntillation Detection And Ranging), that uses correlations of slopes and scintillation indexes recorded on a Shack-Hartmann from two separated stars. CO-SLIDAR leads to an accurate Cn2 retrieval for both low and high altitude layers. Here, we present an end-to-end simulation of the Cn2 profile measurement. Two Shack-Hartmann geometries are considered. The detection noises are taken into account and a method to subtract the bias is proposed. Results are compared to Cn2 profiles obtained from correlations of slopes only or correlations of scintillation indexes only.

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Juliette Voyez, Clélia Robert, Vincent Michau, Jean Marc Conan, Thierry Fusco. 2012-07-19. Accurate measurement of Cn2 profile with Shack-Hartmann data. https://doi.org/10.1117/12.925356

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