The Dome C: A unique site for high-contrast imaging and extrasolar planet searching with a large telescope

The Dome C should benefit from an outstanding atmospheric quality during the night due to catabatic wind conditions (wind speed ~ 2 m s-1, r0 ~ 0.3 m). From analytical and numerical simulations, we show that these seeing conditions are very advantageous for high-contrast imaging and coronagraphic search of exoplanets in the near-IR with adaptive optics (AO): from the Dome C, the planet SNR is 4 times greater than from Mauna-Kea. For these reasons, the Dome C seems to be the natural site for a Planet-Finder consisting in a 2–8 m (possibly off-axis) monolithic telescope equipped with a fast and extreme AO (f ~ 1–2 kHz, f ~ cm), a low-aliasing wave-front sensor (WFS), a coronagraph and a speckle-noise subtraction. In these optimal conditions, a 3.6 m and a 8.2 m-telescope can respectively detect a Jupiter-size and an Earth-size planet at 10 pc in 10h in J band. Lastly, a 15–30 m ELT located at the Dome C could perform fast spectral analysis of Earth-like planets for biomarker searching