Characterizing Exoplanets and Brown Dwarfs With JWST

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1 Characterizing Exoplanets and Brown Dwarfs With JWST C. Beichman NASA Exoplanet Science Institute, Jet Propulsion Laboratory, California Institute of Technology On Behalf of the NIRCam Exoplanet Team September 25, 2015 Copyright 2016 California Institute of Technology. Government sponsorship acknowledged.

2 Major Themes for Exoplanets 1. Coronagraphic Imaging of Young Planets Determine atmospheric composition and physical properties to understand formation mechanism of exterior planets Extend to lower mass limits compared to ground based observations 2. Spectroscopy of Young Planets Determine atmospheric composition and physical properties to understand formation mechanism of exterior planets 3. Survey nearby young M stars Provide census of Jovian mass planets at few 10s of AU 4. Coronagraphic Imaging of Debris Disks Assess composition and structure of disks, e.g. H2O and other ices Search for planets shepherding or sculpting disks 5. Transit Spectroscopy of Mature Planets Determine atmospheric composition and physical properties to understand formation mechanism of interior planets 6. Observations of Brown Dwarfs Understand atmospheres of cool, low mass brown dwarfs as analogs for Jovian mass exoplanets

3 C. Beichman, John Krist, Marie Ygouf, Jeremy Lebreton, Adam Burrows (NIRCam) P-O Lagage, Camilla Danielski (MIRI) Mark Clampin, Remi Soummer et al (Telescope Team) CORONAGRAPHIC IMAGING OF KNOWN PLANETARY SYSTEMS

4 JWST Coronagraph More Sensitive Than Ground at 3-15 um - 3 Log RatioL HContrast MIRI 11 um TFI/NRM 4.4 um NIRCam 4.4 um Spot P1640/GPI/SPHERE 1.65um Keck Vector Vortex at L 5λ/D at 3.5 and 4.8 µm - 8 TMT 1.65 um HarcsecL Theta NIRCam MIRI

5 HD95086, Coronagraphic Observations Observe ~5 known planetary systems with the NIRCam and MIRI coronagraphs to recover physical and atmospheric properties Search for lower mass planets down to ~ MJup Select targets in angular separation range 0.4-3, masses<13 M jup Moonshot planet searches: Fomalhaut, Vega, beta Leo, eps Eri 2 HD95086, λ=2.100 µm, φ=1.054 mjy 2 λ=4.100 µm, φ=2.418 mjy 1 1 arcsec 0 arcsec arcsec arcsec Easy: HD R = 0.6, Δmag 9.2 (L 3.8 um) Hard: HD131399, R=0.84, Δmag=9. Binary at 3!

6 Coronagraphic Observations Monte Carlo analysis over broad range of masses, ages, shows NIRCam, e.g. F210M & F250M (methane), F300M, F335M (CH4), F430M (CO2), and F460M (CO), + MIRI (F1065C, F1140C, F1550C) yields masses, radii, entropy, etc to 10% for known planets. Spiegel and Burrows 2012

7 Is HR8799 Unique? Moon Shot Targets Fomalhaut 1 MJup Beta Leo 0.3 MJup Eps Eri 0.3 MJup Vega 1MJup 5-6 September 2016 ExoFrontiers Cambridge 7

8 Direct Spectroscopy HR8799b Konopacky et al 2013 of Exoplanets At separations >1-2 use the NIRSpec IFU to obtain R~1,000-3,000 spectrum of HR8799 and 2MASS 1207 planets at 3-5 µm At separations beyond 5-10 study planets directly at high resolution with NIRSpec and MIRI LRS/MRS NIRSPEC IFU

9 Potential Imaging and Spectroscopy Targets Model masses <10 Mjup separation between 0.5 (>4 λ/d at 3.5 um) and <2-3 (direct spectroscopy becomes possible). Program is closely coordinated with European MIRI team

10 Mike Meyer, Josh Schleider (NIRCam) SURVEY OF NEARBY YOUNG M STARS October 24, 2016 JWST Montreal 10

11 M Star Survey Kepler & microlensing suggest abundant small planets orbiting M stars NIRCam coronagraphy can reach few M Uranus for <150 Myr, 15 pc planets. NIRCam probes AU, close to CO snow line favored for formation of ice giants NIRCam survey of ~10 objects at F444W at 3.5 hr/object and F322W2 to veto stars and galaxies

12 C. Beichman, Jeremy Lebreton (NIRCam) Andras Gaspar, George Rieke, Kate Su (MIRI) CORONAGRAPHIC IMAGING OF DEBRIS DISKS 24 October 2016 JWST Montreal 12

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14 Illustrative Program

15 Tom Greene, Jonathan Fortney, Jonathan Fraine, E. Schlawin, Mike Line (NIRCam) P-O Lagage (MIRI) Nikole Lewis (STScI/Telescope Team) TRANSIT SPECTROSCOPY OF KNOWN PLANETARY SYSTEMS

16 The many JWST spectroscopic modes Christiansen / Beichman Numerous modes for transits and direct (IFU) exoplanet spectroscopy Covering µm requires 2 4 separate transits or eclipses 16

17 Simulated JWST Transmission Spectra (1 transit) 5-6 September 2016 ExoFrontiers Cambridge 17

18 Simulated JWST Emission Spectra (1 eclipse) 5-6 September 2016 ExoFrontiers Cambridge 18

19 Retrieval Results: Warm Neptune Gasses M. Line CHIMERA Models & retrievals (Greene+ 2016) Priors 5-6 September 2016 JWST Montreal 19

20 Illustrative NIRCam+MIRI Transit Program 5-6 September 2016 JWST Exoplanets Montreal 20

21 Tom Roelling, C. Beichman, Tom Greene (NIRCam) David BarradoNavascués (MIRI) Rene Doyon, David Lafrenière, Albert Loic, Doug Johnstone (NIRISS) Catarina Alves de Oliveira (NIRSpsc) OBSERVING COOL BROWN DWARFS AS EXOPLANET ANALOGS

22 Y dwarfs As Exoplanet Analogs 24 known WISE Y dwarfs have 750< T eff <500 K, 5-10 M jup Formation in quiescent dense cores or ejected from disks of more massive stars Valuable for modeling of exoplanet atmospheres Or Low Mass End of IMF?

23 NIRCam, MIRI, NIRSpec Program for Y Dwarfs Select 10 closest/ coldest, in binary systems, rapid rotators, hotter analogs to young planets NIRCam & MIRI photometry to for SED àteff and luminosity NIRSpec and MIRI spectra to characterize late T and Y NIRISS/NRM Imaging to search for lower mass companions at few AU separation

24 WISE J Faint WISE object with a high proper motion (8.1 /yr) Coldest (~250K) & nearest (2.2 pc) Y-dwarf, 3-10 M jup Water clouds may be needed to make sense of SED

25 Conclusions GTOs will take advantage of JWST multi-wavelength capabilities to carry out coordinated program of exoplanet science --- do a small number of objects well! Lots of room for other investigations in all aspects of exoplanet research Exoplanets represent one of four JWST goalsà25% of JWST time, but depends on YOU writing great proposals 25