Barcelona, September 14, 20091 SCIENTIFIC OUTPUT OF SINGLE APERTURE IMAGING OF EXOPLANETS Raffaele...

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Barcelona, September 14, 2009 1

SCIENTIFIC OUTPUT OF SINGLE APERTURE IMAGING

OF EXOPLANETS

Raffaele Gratton, INAF-OAPD, IAnthony Boccaletti, LESIA-OAPM, FMariangela Bonavita, INAF-OAPD, ISilvano Desidera, INAF-OAPD, IMarkus Kasper, ESO, DFlorian Kerber, ESO, D

Outline

• Introduction: direct imaging of planets, no longer a dream!

• What planets can be observed in the near-mid term• Statistics:

– Mass distribution– Orbits and system parameters

• Spectroscopy and atmosphere composition• Synergies with other techniques dynamical masses

– Radial velocities– Astrometry– Transits

No longer a dream !2M1207 5 MJ 46 AU

GQ Lup 17 MJ 100 AU

AB Pic 14 MJ 248 AU

CHRX73 12 MJ 210 AU

HN Peg 16 MJ 795 AU

DH Tau 12 MJ 330 AU

RSX 1609 8 MJ 330 AU

Detection was made possible because :

- small mass ratios (contrast is lower)- young ages (planet is brighter)- large physical / angular separations

Fomalhaut < 3 MJ 120 AU

HR8799 b 7 MJ 68 AU

HR8799 c 10 MJ 38 AU

HR8799 d 10 MJ 24 AU

ProblematicPlanets are faint and close ….

109 = 1 milliard

106 = 1 million

Reflected light Thermal emission

• Ground based 8m telescopes (2011-)– Hi-Ciao (Subaru) – SPHERE (VLT) – GPI (Gemini) (http://gpi.berkeley.edu/)

• JWST (2014-)– <5 μm: NIRCAM/TFI (http://ircamera.as.arizona.edu/nircam/)– >5 μm: MIRI (http://www.roe.ac.uk/ukatc/consortium/miri/index.html)

• 1.5 m class space coronagraphs (??)– PECO: Guyon et al. 2008, SPIE, 7010, 70101Y– EPIC: Clampin et al. 2006, SPIE, 6265, 62651B; Lyon et al. 2008, SPIE, 7010,

101045– ACCESS: Trauger et al. 2008, SPIE, 7010, 701029– SEE-COAST: http://luth7.obspm.fr/SEE-COAST/SEE-COAST.html

• ELT Instruments (>2018-)– NIR: EPICS (E-ELT), PFI (TMT), HRCAM (GMT)– MIR: METIS (E-ELT: Brandl et al. 2008, SPIE ), MIRES (TMT), MIISE (GMT)

Single aperture planet imagers of the next future

Niches: Contrast, Wavelength, IWA

Year Contrast Wavelength (μm)

IWA (arcsec)

Ground based 8m 2011 10-7 0.9-1.7 0.08

JWST –NIRCAM

2014 10-5

2.1-4.6

0.3-0.6

1.5 m Space Coronagraphs

? 10-9-10-10 0.3-1.3 0.08

ELT’s – EPICS (NIR)

METIS (MIR)

>2018 10-8-10-9

0.9-1.7

2.5-20

Barcelona, September 14, 2009

Observable planets: methodology - inputsSTELLAR PARAMETERS (MStar (Msun), d (pc), Age (Myr), etc.) from two samples of real stars: • Young sample (Age < 500 Myrs, d<100 pc), ~1200 stars • Nearby sample (d < 20 pc) ~600 stars

PLANET PARAMETERS: • Mpsini (MJ) and P (days) randomly generated using the distributions from Cumming et al. 2008, extrapolated up to periods corresponding to a = 40 AU (for MStar = 1 Msun) and scaled with the stellar mass• 0.0 < e < 0.6 generated following the observed RV distribution• All the orbital elements (including inclination), randomly generated using uniform distributions

MONTE-CARLO SIMULATION TOOL: • MESS (Multi-purpose Exo-planet Simulation System) see Bonavita et al.(2009) in prep.

DETECTION LIMIT CURVES:• Direct Imaging (SPHERE, GPI, EPICS, METIS, JWST, Space Coronagraphs)• Radial velocity (HARPS, EXPRESSO, CODEX)• Astrometry (GAIA)

Observable planets: methodology - outputs

DERIVED PLANET PARAMETERS:

• Semi-major axis (AU) and projected separation (arcsec) evaluated assuming Distance and Mass of each star

• Radius (RJ) estimated following the approach of Fortney et al. (2007)

• Teff (K) estimated using the models by Sudarsky et al. (2001)

• Intrinsic luminosity obtained using the models by Baraffe et al. (2003)

• Reflected luminosity in visible and NEAR-IR (V, H, K, L Band) obtained scaling the Jupiter luminosity with planet semi-major axis and radius

• Reflected luminosity in MID-IR (λC = 11.4 μm) obtained assuming a black body emission at T = Teff and λ = λC

• Radial Velocity Semi-amplitude (m/s)

• Astrometric Signature (mas)

SYNTHETIC PLANET POPULATION: • 5 planets per star (mass>0.7 MEarth), randomly extracted from a set of 10.000 combinations of planet parameters

CHARACTERISTICS OF DETECTABLE PLANETS• Contrast vs projected separation• Mass vs Semi-major Axis• Radial velocity signal (K(RV)) vs Period• Astrometric Signature vs Period

Planets observable with Sphere and GPI (2011-)

Nearby stars (<20 pc) Young stars (<5 108 yrs)

Tens of young giant planets at rather large separations

Planets observable with JWST-MIRI (2014-)

Tens of young giant planets at large separationsBut care of disks!

Planets observable with E-ELT+EPICS (2020-)

Many giant planets (both young and old)Tens of Neptune-like planetsA few rocky planets

Planets observable with ~1.5 m dedicated space telescopes (?-)

Many giant planets (both young and old)Tens of Neptune-like planetsA few rocky planets

Planets observable with E-ELT+METIS (2020-)

Many young and a few old giant planets at rather large separations

Mass/semimajor axis distribution of detectable planets: Present

Nearby stars (<20 pc)

CURRENT STATUS

Mass/semimajor axis distribution of detectable planets: 2011-

Young stars (<5 108 yrs)Nearby stars (<20 pc)

Mass/semimajor axis distribution of detectable planets: 2014-

Nearby stars (<20 pc) Young stars (<108 yrs)

Mass/semimajor axis distribution of detectable planets: >2018-

Mass/semimajor axis distribution of detectable planets: ??

Mass/semimajor axis distribution of detectable planets: >2018

Planets in the habitable zone: 2011-2018

Planets in the habitable zone: >2018

Summary

Year Young Giant

Planets

Old Giant

Planets

Neptunes Rocky Planets

Habitable Planets

Ground based 8m

2011- tens few

JWST 2014- tens few

1.5m Space Coronagraphs

? tens tens tens few ??

ELT’s >2018- hundreds hundreds tens few ??

Atmospheric composition

Visible: Space Coronagraphs

Wavelength (μm)

NIR: Sphere, GPI, NIRCAM, EPICS

Wavelength (μm)

MIR: MIRI, METIS

Wavelength (μm)

0.5-30 m spectrum of an isolated 2 MJ planet (Burrows et al.2003, ApJ 596, 587) vs Visible (Space Coronagraphs)

0.5-30 m spectrum of an isolated 2 MJ planet (Burrows et al.2003, ApJ 596, 587) vs NIR (Sphere, GPI, NIRCAM, EPICS)

0.5-30 m spectrum of an isolated 2 MJ planet (Burrows et al.2003, ApJ 596, 587) vs MIR (MIRI, METIS)

Spectroscopic characterization

Spectra at higher resolution than in standard set-up for planet detection will allow a more detailed characterization (for planets detected with high enough S/N)

Some science goals: identification of spectral features, determination of physical parameters (temperature, gravity, chemical composition), cloud process and their variation with time (e.g. for planets in eccentric orbits)

R=3000, R=20000 considered

See Poster by Claudi et al.

Medium resolutionMedium resolution

McLean+2007

High resolution (R=20000) High resolution (R=20000)

R=20000 J band spectrum of a T4.5 BD (Mc Lean+2007), many spectral lines available

Identified H2O lines marked

Planet radial velocity

Earth semi-amplitude: 30 km/s Useful to constrain the planetary orbit if only visual

measurements available, planet-star mass ratio even based on small time baseline

Detection of binary planets, if any Several lines at high resolution, resolved sky lines to be

used as wavelength reference.

Planet rotational velocity

Jupiter: Vrot:12.6 km/s, Saturn: 9.9 km/s, Neptune: 2.7 km/s

Field T dwarfs typically rotate faster (30-50 km/s: McLean et al., Zapaterio Osorio et al. )

R=20,000 corresponds to FWHM=15 km/s, R=3000 to 100 km/s

Possibility of measuring rotational velocity similar to that of Jupiter

Very interesting if coupled with photometric rotational modulation ( Planet radius independent of luminosity; inclination of rotational axis over orbital plane)

Estimate of the number and type of accessible targets using Monte Carlo simulation (R=3000, R=20000)

R=3,000hundreds

R=20,000tens

Number of targets for EPICS

Synergies with radial velocitiesPlanets already discovered from RVs

Very important: planet mass independent of model assumptions!

Synergies with radial velocitiesPlanets already discovered from RVs

Very important: planet mass independent of model assumptions!

RV signal of detectable planets

Astrometric signal of detectable planets

SIM(Beichman et al. 2008)

Potential overlap with PLATO• PLATO: ESA Cosmic Vison proposed mission for the search of transiting planets• Planets down to about 10 MEarth around K and M dwarfs with V=8.5-10 (bright end of

PLATO) can be detected also with EPICS• For K dwarfs, planets in the habitable zone are detectable• Availability of planet spectrum from EPICS and planet radius from PLATO will be

relevant for the physical study of the planets.• For G and F stars (and K and M dwarfs as well) planets at separation larger than that

accessible to PLATO can be detected, allowing to study the outer planetary system of PLATO targets

See talk by Claudi et al.

Barcelona, September 14, 20091 SCIENTIFIC OUTPUT OF SINGLE APERTURE IMAGING OF EXOPLANETS Raffaele...

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