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B. Macintosh (LLNL), J.R. Graham (UCB), A. Ghez (UCLA), P. Kalas, J. Lloyd (UCB), R. Makidon (STScI), S. Olivier (LLNL), J. Patience (Caltech), M. Perrin (UCB), L. Poyneer (LLNL), S. Severson, A. Sheinis (UCSC), A. Sivaramakrishnan (STScI), M. Troy, J. Wallace (JPL), J. Wilhelmsen (LLNL)
Direct detection of photons emitted or reflected by extrasolar planets is the next major step in extrasolar planet studies. Current adaptive optics (AO) systems, with <300 subapertures and Strehl ratio ~ 0.4-0.7, can achieve contrast levels of ~106 at 2" separations; this is sufficient to see very young planets in wide orbits but insufficient to detect solar systems more like our own. Contrast levels of 107 - 108 in the near-IR are needed to probe a significant part of the extrasolar planet phase space.
The NSF Center for Adaptive Optics is carrying out a design study for a dedicated ultra-high-contrast "Extreme" adaptive optics system for an 8-10m telescope. With ~3000 controlled subapertures it should achieve Strehl ratios > 0.9 in the near-IR. Using a spatially filtered wavefront sensor, the system will be optimized to control scattered light over a large radius and suppress artifacts caused static errors. We predict that it will achieve contrast levels of 107-108 around a large sample of stars (R<7-10), sufficient to detect Jupiter-like planets through their near-IR emission over a wide range of ages and masses. The system will be capable of a variety of high-contrast science including studying circumstellar dust disks at densities a factor of 10-100 lower than currently feasible and a systematic inventory of other solar systems on 10-100 AU scale.
This work was supported by the NSF Science and Technology Center for Adaptive Optics, managed by UC Santa Cruz under AST-9876783. Portions of this work was performed under the auspices of the U.S. Department of Energy, under contract No. W-7405-Eng-48.
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Bulletin of the American Astronomical Society, 34, #4
© 2002. The American Astronomical Soceity.