اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدClio: a 3-5 micron AO planet-finding camera
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Clio is an adaptive-optics camera mounted on the 6.5 meter MMT optimized for diffraction-limited L and M-band imaging over a ~15 field. The instrument was designed from the ground up with a large well-depth, fast readout thermal infrared (~3-5 micron) 320 by 256 pixel InSb detector, cooled optics, and associated focal plane and pupil masks (with the option for a coronograph) to minimize the thermal background and maximize throughput. When coupled with the MMTs adaptive secondary AO (two warm reflections) systems low thermal background, this instrument is in a unique position to image nearby warm planets, which are the brightest in the L and M-band atmospheric windows. We present the current status of this recently commissioned instrument that performed exceptionally during first light. Our instrument sensitivities are impressive and are sky background limited: for an hour of integration, we obtain an L-band 5 sigma detection limit of of 17.0 magnitudes (Strehl ~80%) and an M-band limit of 14.5 (Strehl ~90%). Our M-band sensitivity is lower due to the increase in thermal sky background. These sensitivities translate to finding relatively young planets five times Jupiter mass at 10 pc within a few AU of a star. Presently, a large Clio survey of nearby stellar systems is underway including a search for planets around solar-type stars, M dwarfs, and white dwarfs. Even with a null result, we can place strong constraints on planet distribution models.
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