FANTEÏ-CAUJOLLE , Y.

Wide-Field Adaptive Optics (WFAO) have been proposed for the next generation of telescopes. In order to be efficient, correction using WFAO require knowledge of atmospheric turbulence parameters. The structure constant of index-of-refraction fluctuations (C2 N ) being one of them. Indirect methods implemented in instruments as SCIDAR, MASS,...

We present a generalized differential image motion monitor (GDIMM). It is a compact instrument dedicated to the measurement of four parameters of optical turbulence: seeing, isoplanatic angle, coherence time and wavefront coherence outer scale. The GDIMM is based on a small telescope (28 cm diameter) equipped with a three-hole mask at its...

The optical turbulence measurement and characterization has become an essential information for optical link (telecommunication, telemetry, time transfert, ...) and for high-angular resolution imagining in astron- omy. For example, it has an impact on the quality and on the bit error rate of optical communication signals and it decrease the...

International audience

International audience

International audience

With the prospect of the next generation of ground-based telescopes, the extremely large telescopes, increasingly complex and demanding adaptive optics systems are needed. This is to compensate for image distortion caused by atmospheric turbulence and fully take advantage of mirrors with diameters of 30-40 m. This requires a more precise...

Aims: The Antarctica Search for Transiting Extrasolar Planets (ASTEP), an automatized 400 mm telescope located at Concordia station in Antarctica, monitored β Pictoris continuously to detect any variability linked to the transit of the Hill sphere of its planet β Pictoris b. The long observation sequence, from March to September 2017, combined...