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Clio: 3-5  m planet-finding AO camera

Clio: 3-5  m planet-finding AO camera. First planet. Ari Heinze (Steward Observatory) Collaborators: P. Hinz (Steward), S. Sivanandam (Steward), M. Freed (Optical Sciences), A. Breuninger (Steward). 3-5  m Window. High Background Warm Telescope Variable and High Sky Flux

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Clio: 3-5  m planet-finding AO camera

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  1. Clio: 3-5 m planet-finding AO camera First planet Ari Heinze (Steward Observatory) Collaborators: P. Hinz (Steward), S. Sivanandam (Steward), M. Freed (Optical Sciences), A. Breuninger (Steward)

  2. 3-5 m Window • High Background • Warm Telescope • Variable and High Sky Flux • Atmospheric Throughput • High Duty Cycle Readout • Large Well-depth Detector • Better contrast ratios • M-band bump in planets only weakly dependent on age • Observing catalogue includes nearby moderate age stars • Better AO correction Near/Thermal IR Spectra of known extrasolar giant planets around G-type stars. Mass range from 1-10 MJup.M-band bump present irrespective of age and mass, though near-IR flux decreases steeply with age. (Burrows et al. 2004) SPIE 2006 - Clio - Page 2

  3. Clio Design • Diffraction-limited imaging from H through M-bands • 3 imaging modes: f/35 (H and K-bands),f/20 (L and M-bands), and pupil imaging (for alignment of cold-stops) modes • 320256 large well-depth, high throughputInSb array optimized for 3-5 m imaging (Indigo Systems Inc.) • Cooled optics (77K), baffling, and cold stops to minimize instrument thermal background • Coronographic option built in (have ability to add field and pupil stops and PSF shaping wave plates) SPIE 2006 - Clio - Page 3

  4. Clio Schematic Schematic of Clio in f/20 mode with ray trace. SPIE 2006 - Clio - Page 4

  5. Detector Performance Detector Noise Map Detector Characteristics SPIE 2006 - Clio - Page 5

  6. Observing Strategy • To remove high sky background: • Nod the telescope a few arcseconds after each exposure and close AO loop • Subtract nod pairs • To improve duty cycle • Coadd batches for ~20 images for every exposure • To improve sensitivity • Integrate in the L’ and M-band until sky flux fills ~1/2 of full well • Typical integrations: 100 ms (M-band); 1500 ms (L’-band) • Sky background-limited and detector noise is negligible • To mitigate long-lived speckles • Keep instrument derotator fixed allowing the sky to rotate • Rotate images by the parallactic angle to correct orientation during processing • Static speckles stay fixed on chip and are blurred out by rotation SPIE 2006 - Clio - Page 7

  7. On-sky Performance • Reach quoted 10background-limited detection values at separations greater than 1.5” from the central star (after PSF subtraction and unsharp mask) • L’ ~ detect 5 Mjup 0.5 Gyr old planet at 10 pc • M ~ detect 10 Mjup 0.5 Gyr old planet at 10 pc • Have better L’ sensitivity • Focus initial search in L’ • M-band follow up observations to obtain color and establish nature of source • Very stable PSF • Good subtraction of PSF, better contrast Clio Observational Parameters S T M SPIE 2006 - Clio - Page 8 PSFs of 5 different L’ exposures

  8. Vega in M-band Clio 672 s M-band image (unsharp masked) Dust model and predicted planet position (Wilner et al. 2002) First Light Observations (ApJ, accepted) SPIE 2006 - Clio - Page 9

  9. Vega Sensitivity Metchev et al. (ApJ 582, 1102) using Palomar at H-band Macintosh et al. (ApJ 594, 538) using Keck at K-band 10 Mjup fake planet at 20 AU Companion mass limit (5 sigma) Expected Planet? Limit from 5 minute observation at M band Separation (arcsec) 1 arcsec Vega Planet Sensitivity Comparison Vega Fake Planet SPIE 2006 - Clio - Page 10

  10. GJ450 in L’-band • Stellar properties: • M dwarf • 1 Gyr (X-ray) • 9 pc • Observation: • 5355 s L’ exposure • No detection • Sensitivity Test: • Monte Carlo simulation • 10 planets • Blind test • Recovered all planets reliably Nod artifact 2 arcsec GJ450 Exposure with fake 10 planets

  11. GJ450 Monte-Carlo Planets Continued

  12. GJ450 Sensitivity Background limited 6 Mjup PSF subtracted 10Planet Mass Sensitivity Contrast Ratio in L’-band SPIE 2006 - Clio - Page 12

  13. PSF Suppression • PSF sidelobes are over 7 magnitudes fainter at 3 λ/D away • The pattern is stable and can be reliably subtracted off to reach the limit of the sky background • PSF suppression is easier at M-band where Strehls are typically 90% SPIE 2006 - Clio - Page 13

  14. Science Programs • 6 pc M dwarf search [observed 4 stars] • M through F star search (emphasis on solar-type stars) [observed 20 of 50 stars] • A-type star search [this trimester] • White dwarf search [this trimester] • Vega search [observed twice] • T-dwarf photometry [this trimester] SPIE 2006 - Clio - Page 14

  15. Vega, M-band, 2850 sec (April)

  16. Vega, M-band, ~1hr (June)

  17. ξ Boo, L’, ~1 hr

  18. ξ Boo, M, ~1 hr

  19. BD+60 1417, L’, ~1hr

  20. BD+60 1417, L’, ~1hr

  21. BD+60 1417, L’, ~1hr

  22. BD+60 1417, Ks, ~1hr

  23. Stay tuned… The first direct image of a mature extrasolar planet orbiting a normal star may be only months away… And may well happen at the MMT.

  24. Design Simulations MONTE CARLO SIMULATIONS Take spectra of 100 Myr - 5 Gyr old planets, and consider: • Instrument Throughput • Atmosphere • Sky Background • Telescope Emissivity (10%) • Strehl Ratio • Planet Photon Noise • Detector Dark Current/Read Noise Best Filter Bandpass: M-band Best Bandpass S/N Plot. (Freed et al. 2004)

  25. Outline • Why 3-5m? • Clio Design • Detector Performance • Clio On-sky Performance • Latest Scientific Results • Planet-finding Sensitivities • Science Program SPIE 2006 - Clio - Page 2

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