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CHEOPS
Science Adaptive
Optics
ZIMPOL Near-Infrared
3D Spectrograph
CHaracterizing Extrasolar planets by Opto-infrared Polarimetry and Spectroscopy

The CHEOPS project aims at constructing a 2nd generation instrument for one of ESO's VLTs for direct detection of extrasolar giant planets. The phase-A feasibility study of this project ended on November 2 2004. For the extraordinarily demanding task of overcoming a contrast of at least 18 magnitudes across a separation of half a second of arc, the instrument requires

XAO
A new, adaptive optics system of extremely high order to provide the required image quality.

Contrast Enhancement
The contrast between a star and an accompanying planet is too large for direct imaging with even the most sophisticated AO system. CHEOPS will enhance the achievable contrast by two differential imagers, a polarimetric one and a spectroscopic one.

Detailed Knowledge on Targets
To optimize the chances of detection using the two differential images, detailed knowledge on the properties of planetary atmospheres - of both young and warm, and of mature planets like our own Jupiter is required. Spectra of model atmospheres and models on polarization properties have to be developed and verified. All states of planetary development and also of the central stars need to be well known.

New Methods of Observation
The number of candidates is limited to a few hundred targets due to distance and guide star brightness limitations. On the other hand the demanding XAO system will only be able to deliver its top performance in the best (~30%) seeing conditions. This requires a detailed planning scheme to execute the survey for nearby exoplanets.
Science
CHEOPS aims at direct detection, identification and characterization of extrasolar mature and young planets. More...
XAO
The new xetreme AO system will operate a 1600 actuator DM at 2kHz using a pyramid sensor at 0.8 micron. More...
ZIMPOL
is a differential polarimetric imager capable of measuring polarization degrees down to 10-5 per resolution element. More...
The NIR IFU
is an integral field spectrograph for the very-near ("opto-") infrared. More...