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Directly Imaging and Characterizing Extrasolar Planets at High Contrast. Thayne Currie (U. Toronto, NAOJ Aug 2014 !) Adam Burrows (Princeton), Nikku Madhusudhan (Cambridge), Ryan Cloutier (U. Toronto) + SEEDS Collaboration. Extrasolar Planets. Mayor and Queloz (1995).
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Directly Imaging and Characterizing Extrasolar Planets at High Contrast Thayne Currie (U. Toronto, NAOJAug 2014!) Adam Burrows (Princeton), NikkuMadhusudhan (Cambridge), Ryan Cloutier (U. Toronto) + SEEDS Collaboration
Extrasolar Planets Mayor and Queloz (1995) Mayor and Queloz (1995) Charbonneau et al. (2000)
E V (Oakley & Cash 2009; Kaltenegger et al. 2007)
Direct Imaging 1. Challenges: How to overcome them? 2. What we have learned so far? (e.g. atmospheres) 3. The Near Future?
Adaptive Optics Sharper Images, Helps Us Separate Planet Light from Starlight (C. Beichman, A. Tanner; Palomar PALM-3K)
Why Directly Imaging Planets is Hard HR 8799 (Keck/NIRC2 H band; July 2005, Currie et al. 2012a)
Observing Techniques for Imaging Planets: “Angular Differential Imaging” (ADI)
Post-Processing Techniques for Imaging Planets: A-LOCI (T. Currie 2012, 2013, 2014) Science Image Ref.”Image” weights Aweighted, ‘locally optimized combination of (reference) images’ (LOCI) (Lafreniere et al. 2007)
Detecting Planets with A-LOCI Increased planet throughput, more reliable photometry, (sometimes) slight increase in SNR
Detecting Planets with A-LOCI (T. Currie 2012,2013, 2014) Truncate elements in covariance matrix during matrix inversion (similar to truncation on # principle components in PCA) ``Speckle filtering”
Exoplanet Direct Imaging with ADI and A-LOCI (ex. HR 8799) A-LOCI (May 2012) Currie et al. (2012a) Keck/NIRC2 (near-IR), July 2005
Exoplanet Direct Imaging with ADI and A-LOCI (ex. HR 8799) Keck/NIRC2 (mid IR), November 2012 A-LOCI (current) (Currie et al. 2014, in prep.) Subaru/IRCS (mid-IR), July 2012 VLT/NaCo (near-IR), October 2010
Directly Imaged Planetary Systems HR 8799 bcde (Marois et al. 2008, 2010; Kalas et al. 2008; Lagrange et al. 2010; Currie et al. 2014a,b; Rameau et al. 2013; Kuzuhara et al. 2013)
Unpublished … T. Currie, et al. in progress Many candidates to reimage!
Current Limits on Imaging Planets: Young super-jovian planets at > 10 AU (Skemer et al. 2014; Currie et al. 2014 in prep)
A “Scaled-Up” Version of the Solar System? HR 8799 – hotter, more massive and brighter than the Sun … (Marois et al. 2010)
Orbits of Directly-Imaged Planets (Nov. 2009 to Nov. 2012) (Marois et al. 2010; Currie et al. 2012, 2014 in prep.; Mede, Currie et al. 2014 in prep.)
Atmospheres of Directly-Imaged Planets (Currie et al. 2011a, 2014abc) ROXs 42Bb HR 8799 bcde
Directly-Imaged Planets: Should Look like Field Brown Dwarfs? Brown Dwarf Atmosphere Models: similar range in Teff young gas giant planet atmospheres? (Burrows et al. 2006)
Near-Infrared Colors of Young Directly-Imaged Planets Currie et al. (2011a, 2013, 2014)
Fitting HR 8799b and c Data with Standard Atmosphere Models Used for Brown Dwarfs FAIL! Currie et al. (2011a)
Thicker clouds for Planets (not in Field Brown Dwarfs) = Huge difference From Atmosphere Models in Currie et al. (2011a)
Young Gas Giants have Thick(Patchy?) Clouds HR 8799c HR 8799bcd(e?) – ~ 5—7 Mj, Teff ~800-1100 K, log(g) ~ 3.8-4.3 Currie et al. (2011a); Madhusudhan, Burrows, and Currie (2011)
Spectra of Directly-Imaged Planets ROXs 42Bb (Currie et al. 2014a,b)
Spectra of Directly-Imaged Planets H2(K) H2 Index (2.17-2.24 micron flux ratio) surface gravity tracer Low surface gravity thick clouds? (Currie et al. 2014a,b; Currie et al. 2011a, 2013)
Direct Imaging in the Near Future: SCExAO Project (2014-) • 1. Extreme AO imager for Subaru • (PI O. Guyon). • Strehl Ratio (1.6 mic) ~ 90% 2. Undergoing on-sky testing/engineering runs; full power ~ late 2014? IFU spectrograph (CHARIS) • 3. Exoplanet Imaging • as follow-on to SEEDS
What Can SCExAO Do? 15 Myr old; 30 pc away
SCExAO vs. First-Light TMT SCExAO: Likely best exoplanet imager in North until 2nd gen TMT (~2030) NFIRAOS estimates from Marois et al. 2012
Summary 1. Challenges: How to overcome them? 2. What we have learned so far? (e.g. atmospheres) 3. The Near Future?
SCExAO: A Precursor to TMT Exoplanet Imaging PIAA Coronagraph – planet imaging at ~ lambda/D “Speckle Nulling” Martinache & Guyon 2011; Jovanovic et al. 2013; Martinache et al. 2014