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arXiv · 0907.0326

Extreme coronagraphy with an adaptive hologram Simulations of exo-planet imaging

D. Ricci·H. Le Coroller·A. Labeyrie
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Abstract

Aims. We present a solution to improve the performance of coronagraphs for the detection of exo-planets. Methods. We simulate numerically several kinds of coronagraphic systems, with the aim of evaluating the gain obtained with an adaptive hologram. Results. The detection limit in flux ratio between a star and a planet (Fs/Fp) observed with an apodized Lyot coronagraph characterized by wavefront bumpiness imperfections of lambda/20 (resp. lambda/100) turns out to be increased by a factor of 10^3.4 (resp. 10^5.1) when equipped with a hologram. Conclusions. This technique could provide direct imaging of an exo-Earth at a distance of 11 parsec with a 6.5m space telescope such as the JWST with the optical quality of the HST.

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D. Ricci, H. Le Coroller, A. Labeyrie. 2009-07-02. Extreme coronagraphy with an adaptive hologram Simulations of exo-planet imaging. https://doi.org/10.1051/0004-6361%2F200811529

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