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New Observafions of Fomalhaut, Beta Pic and HR 4796A with HST And Paul Kalas, Planets Across HR Diagram, Cambridge, 2014 New Observa+ons of Fomalhaut, Beta Pic and HR 4796A with HST and GPI Paul Kalas University of California, Berkeley July 30, 2014 Cambridge University, UK Collaborators: James Graham (UC Berkeley), Mike Fitzgerald (UCLA), Gaspard Duchene (UC Berkeley), Marshall Perrin (STScI), Bruce Macintosh (Stanford), Mark Clampin (NASA GSFC), and the GPI Instrument and Science Teams NASA NNX11AD21G, NSF AST-0909188, University of California LFRP-118057, GO-11818, GO-12576, GO-13037 1 Paul Kalas, Planets Across HR Diagram, Cambridge, 2014 Unsolved Problems: Direct detections of planets beyond 5 AU 2 Paul Kalas, Planets Across HR Diagram, Cambridge, 2014 Direct planet images in last 10 years. GQ Lup 2M1207 AB Pic Fomalhaut HR 8799 Beta Pic HD 95086 Kalas et al. 2008 Marois et al. ’08,’10 Lagrange et al. 2009 Rameau et al. 2013 Also GJ 504 (Kuzuhara et al. 2014) and HD 106906 (Bailey et al. 2014) 3 In Suzanne Aigrain’s talk you saw the non detection statistics – the detections above are rare. Paul Kalas, Planets Across HR Diagram, Cambridge, 2014 The puzzles of Fomalhaut b HR 8799 Fomalhaut Marois et al. ’08,’10 Kalas et al. 2008 Detected in the NIR, as expected. Detected only in the optical, unexpected. Low eccentricity orbits, as expected. High eccentricity, belt-crossing, unexpected. 4 Paul Kalas, Planets Across HR Diagram, Cambridge, 2014 AVer discovery With HST/ACS in 2004 & 2006, folloW-up With STIS in 2010 and 2012 shoWed that the orbit is highly eccentric. e = 0.8 - 0.9 Confirmed in Beust et al. 2014 Kalas, Graham, Fitzgerald & Clampin 2013 5 Paul Kalas, Planets Across HR Diagram, Cambridge, 2014 2013 Epoch is the fiVh epoch of detec]on Kalas et al. 2014, in prep. High e confirmed. Periastron ~10 AU Problem: In several years may be undetectable in the optical as it enters the same line of sight as the belt’s dust-scattered light. 6 Paul Kalas, Planets Across HR Diagram, Cambridge, 2014 Near future observaons #1 A_empt in 2015 to resolve the 10 AU “ice-line” belt in scaered light With HST/STIS undisturbed or disturbed? Pearce & Wyatt 2014 See also Faramaz et al. 2014 7 “2-belt systems”, See posters #23, Morales et al. & #37 Su et al. Paul Kalas, Planets Across HR Diagram, Cambridge, 2014 Near future observaons #1 A_empt in 2015 to resolve the 10 AU “ice-line” belt in scaered light With HST/STIS undisturbed or disturbed? Pearce & Wyatt 2014 See also Faramaz et al. 2014 8 Paul Kalas, Planets Across HR Diagram, Cambridge, 2014 Near future observaons #2 Coronagraphic study of Fomalhaut C With HST/STIS Undisturbed or disturbed disk? Kennedy et al. 2014 Too faint for GPI 9˚ x 9˚ field 9 Paul Kalas, Planets Across HR Diagram, Cambridge, 2014 HoW do you increase the sample of directly imaged outer planets to be_er understand these issues? Dedicated coronagraphic instruments coupled with adap+ve op+cs. 1. Gemini Planet Imager (Gemini South 8 m, Chile; PI Macintosh) 2. SPHERE (VLT 8 m, Chile) 3. MagAO (Magellan 6.5 m, Chile) 4. HiCIAO/SCExAO (Subaru 8 m, Hawaii) 5. P1640 (Palomar 5 m, California) 10 Paul Kalas, Planets Across HR Diagram, Cambridge, 2014 GPI First Light 11 Paul Kalas, Planets Across HR Diagram, Cambridge, 2014 A remarkable achievement Raw images in ~60 seconds integration. No data processing. No PSF subtraction. Space: HST/STIS Ground: Gemini Planet Imager Perrin et al. 2014, submitted 12 Paul Kalas, Planets Across HR Diagram, Cambridge, 2014 Total Intensity Polarized Intensity Brighter side in both optical and NIR 165˚ 15˚ data. forward Forward scattering direction. 15˚ 165˚ forward Perrin et al. 2014, submitted Fitzgerald et al. 2014, in prep. 13 Paul Kalas, Planets Across HR Diagram, Cambridge, 2014 The scaering proper]es of the HR 4796A ring are more complex than expected: Large par]cles? Not op]cally thin? Perrin, Duchene, Millar-Blanchaer, et al. 2014 (arXiv:1407.2495) Optically thin Mie scattering model for astronomical silicates 14 MCFOST models by Gaspard Duchene Paul Kalas, Planets Across HR Diagram, Cambridge, 2014 Beta Pic b orbit solu]ons and transit probability Star ~ 3.8 mag PA = 211.6˚±0.85˚ Planet Dmag ~ 9 Main Disk Midplane has r = 434 ± 6 mas PA = 209.0˚±0.3˚ a ~ 9 AU (Chauvin et al. 2012) Macintosh, Graham & GPI Instrument Team 2014 (arXiv:1403.7520) i = 90˚.69 ± 0˚.68 4% probability of a transit of the planet in late 2017 15 Paul Kalas, Planets Across HR Diagram, Cambridge, 2014 Direct detections of planets beyond 5 AU 16 Paul Kalas, Planets Across HR Diagram, Cambridge, 2014 Direct detections of planets beyond 5 AU GPI Exoplanet Survey (GPIES): 2014-2018, 600 stars Expect 25 - 50 new direct detection of exoplanets 17 Paul Kalas, Planets Across HR Diagram, Cambridge, 2014 Summary • Fomalhaut With HST (Kalas et al. 2014): STIS 5th epoch detec]on, posi]on approaching the dust belt. NeW HST observaons planned to map the morphology of Fomalhaut A’s inner belt, and Fomalhaut C’s debris disk. Are they dynamically disturbed? • HR 4796A With GPI (Perrin et al. 2014, Fitzgerald et al. 2014): Very unexpected ~40% polarizaon on What Was previously thought to be the back-scaering side of the belt. Large grains? Op+cally thick? • Beta Pic b With GPI (Macintosh et al. 2014): Orbit posi]on angle offset from the main disk midplane, and may be exactly edge- on. Will it transit in late 2017? .
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