Modeling extrasolar planetary atmospheres

Modeling extrasolar planetary atmospheres

Planetary Systems as Potential Sites for LifeSpecial Session SpS6 - Aug. 11th, 11h-11h20

France AllardDirectrice de Recherche, CNRS

Centre de Recherche Astrophysique de Lyon

Planetary Systems as Potential Sites for LifeSpecial Session SpS6 - Aug. 11th, 11h-11h20

France AllardDirectrice de Recherche, CNRS

Centre de Recherche Astrophysique de Lyon

Typical flux distributionTypical flux distribution

Very generally a planet will:

a) reflected stellar light. It dominates at the stellar peak of emission.

b) thermal emission of the rest of the stellar light.

c) thermal emission from the interior (like brown dwarfs).

Very generally a planet will:

a) reflected stellar light. It dominates at the stellar peak of emission.

b) thermal emission of the rest of the stellar light.

c) thermal emission from the interior (like brown dwarfs).

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Web Simulator ONLINE!

• Offers synthetic spectra and thermal structures of published model grids and the relevant publications.

• Computes synthetic spectra, with/without irradiation by a parent star, and photometry for:

main sequence stars

brown dwarfs (1 Myrs - 10 Gyrs)

extrasolar giant planets

telluric exoplanets

• Computes isochrones and finds the parameters of a star by chi-square fitting of colors and/or mags to the isochrones.

• Rosseland/Planck as well as monochromatic opacity tables calculations

http://phoenix.ens-lyon.fr/simulator

NOW OPEN!

Static 1D radiative model: reconstruction of the

surface

Static 1D radiative model: reconstruction of the

surface

Barman, Hauschildt & Allard (ApJ 632, p1132, 2005)Barman, Hauschildt & Allard (ApJ 632, p1132, 2005)

For each block Tint so as all thermal structures meet the same adiabat below the photosphere

night side Teff= 500K

HD209458b

1995K

Orbital PhasesOrbital Phases

Luminosity ratio as a function of orbital phase. 0.0 corresponds to a transit (night side only). 0.5 is when the planet is occulted by the star.

Luminosity ratio as a function of orbital phase. 0.0 corresponds to a transit (night side only). 0.5 is when the planet is occulted by the star.

Barman, Hauschildt &Barman, Hauschildt & Allard (ApJ 632, p.1132, 2005) Allard (ApJ 632, p.1132, 2005)

HD209458b H2O detection!

HD209458b H2O detection!

Barman (ApJ 661, L191, 2007)

Time-dependant 1D radiative(assumes wind velocity)

600K day-to-night contrast!

Time-dependant 1D radiative(assumes wind velocity)

600K day-to-night contrast!

Equatorial cut of the atmosphere between the 10-6 and 10-bar levels for an equatorial wind velocity of a) 0.5 km s-1; b) 1 km s-1; and c) 2 km s-1. The level where condensation of sodium occurs (black line) goes deeper as the night wears on (anti-clockwise) and is deepest at the morning limb. Below 10 bar, the temperature field (not shown here) is uniform and depends only on the bottom boundary condition.

radiative time constant which increases with depth and reaches about 8 h at 0.1 bar and 2.3 days at 1 bar.

Equatorial cut of the atmosphere between the 10-6 and 10-bar levels for an equatorial wind velocity of a) 0.5 km s-1; b) 1 km s-1; and c) 2 km s-1. The level where condensation of sodium occurs (black line) goes deeper as the night wears on (anti-clockwise) and is deepest at the morning limb. Below 10 bar, the temperature field (not shown here) is uniform and depends only on the bottom boundary condition.

radiative time constant which increases with depth and reaches about 8 h at 0.1 bar and 2.3 days at 1 bar.

Iro, Bezard & Guillot (A&A 436, p719, 2005)

Quasi-2D, single layered fluid dynamics

Quasi-2D, single layered fluid dynamics

[Left] Equatorial and polar views of potential vorticity (a flow tracer) in a specific hot Jupiter model from Cho et al. (2003, 2007). Note the prominent circumpolar vortices formed as a result of potential vorticity conservation. [Right] Corresponding zonally averaged wind profile, characterized by a small number of broad jets (three in this case).

Fig 3 of Showman, Menou & Cho (2007)

Cho et al. (2003, 2007)

Radiative (grey) Hydrodynamics

with Rotation!

Radiative (grey) Hydrodynamics

with Rotation!

The temperature at the photosphere of a planet rotating with a period of 3 days. The upper panel shows the distribution over the entire planet, while the lower panel highlights the temperature structure on the night-side from = /2 to = 3/2. A clear day-night delineation persists, despite complicated dynamical structure, due to substantial radiation near the terminators.

Day side extended isotherm: 1200K for a start at 1200K.

Night side has 310 to 500K for a start at 100K.

Jets near terminator: 500K

The temperature at the photosphere of a planet rotating with a period of 3 days. The upper panel shows the distribution over the entire planet, while the lower panel highlights the temperature structure on the night-side from = /2 to = 3/2. A clear day-night delineation persists, despite complicated dynamical structure, due to substantial radiation near the terminators.

Day side extended isotherm: 1200K for a start at 1200K.

Night side has 310 to 500K for a start at 100K.

Jets near terminator: 500K

Dobbs-Dixon & Lin (2007)astro-ph/0704.3269

night side

whole

Hydrodynamical 3D model based on radiative timescales by Iro05

Hydrodynamical 3D model based on radiative timescales by Iro05

Global temperature maps: model atmosphere spanning ∼15 pressure scale heights between the input top layer and the bottom boundary at 3 kbar, using 40 layers evenly spaced in log pressure with a P-T profile generated at evenly spaced longitudes (in 5° increments) and latitudes (in 4° increments) for 72 longitude and 44 latitude points (=3168 P-T profiles). Arrows show the direction and relative magnitudes of winds. Each longitude minor tick mark is 18°, and each latitude minor tick mark is 9°. Each panel uses the same temperature shading scheme.

Strong winds (3-9 km/s = 6500-20000 mph) predicted to form under substellar point - offsets hottest point viewed, shifts phase.

Cooper & Showman (2006)

Global temperature maps: model atmosphere spanning ∼15 pressure scale heights between the input top layer and the bottom boundary at 3 kbar, using 40 layers evenly spaced in log pressure with a P-T profile generated at evenly spaced longitudes (in 5° increments) and latitudes (in 4° increments) for 72 longitude and 44 latitude points (=3168 P-T profiles). Arrows show the direction and relative magnitudes of winds. Each longitude minor tick mark is 18°, and each latitude minor tick mark is 9°. Each panel uses the same temperature shading scheme.

Strong winds (3-9 km/s = 6500-20000 mph) predicted to form under substellar point - offsets hottest point viewed, shifts phase.

Cooper & Showman (2006)

8 km s-1= static

W-to-E 35°

W-to-E 60°

Orbital phase Orbital phase

Planetary emergent flux density (ergs s-1 cm-2 Hz-1) vs. wavelength as a function of orbital phase for equilibrium chemistry. The dashed black curve is the flux of a 1330 K blackbody, which plots behind the dark blue curve at λ > 4 μm. Normalized Spitzer band passes are shown in dotted lines at the bottom and standard H, K, L, and M bands are shown at the top.

Planetary emergent flux density (ergs s-1 cm-2 Hz-1) vs. wavelength as a function of orbital phase for equilibrium chemistry. The dashed black curve is the flux of a 1330 K blackbody, which plots behind the dark blue curve at λ > 4 μm. Normalized Spitzer band passes are shown in dotted lines at the bottom and standard H, K, L, and M bands are shown at the top.

Fortney, Cooper, Showman, Marley, & Freedman (ApJ 652, 746, 2006)

HD189733bHD189733b

Simulations vs transit observations. The overall transmission spectrum is shaped by the water absorption in the infrared (Tinetti et al., 2007b) but methane is needed to explain the NIR (Swain, Vasisht, Tinetti, 2008). At shorter wavelength, the increasing flatness of the spectrum could be explained by hazes. Broad band photometry is not enough to distinguish the different additional molecules.

Figs. 1 & 2 of Tinetti & Baulieu (2008)

2D RHD simulations of cloud formation

in brown dwarf atmospheres

2D RHD simulations of cloud formation

in brown dwarf atmospheres

CO5BOLD models (Bernd Freytag), gas and grains (Mg2SiO4) opacities from Phoenix, cloud model (dust size-bin distribution), nucleation, condensation, coagulation rates, and sedimentation velocity according to Rossow (1978). In red the dust mass density is indicated, while in green the entropy is shown to indicate the convection zone.

CO5BOLD models (Bernd Freytag), gas and grains (Mg2SiO4) opacities from Phoenix, cloud model (dust size-bin distribution), nucleation, condensation, coagulation rates, and sedimentation velocity according to Rossow (1978). In red the dust mass density is indicated, while in green the entropy is shown to indicate the convection zone.

W350 x H80 km2 over 36 hours

QuickTime™ et undécompresseur codec YUV420

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Gravity Waves !!!

EGPs: the CoRoT-3b caseEGPs: the CoRoT-3b case

Temperature inversion in outer layers

Temperature raises above condensation temperature

Dust only forms in the optically thin upper layers

CoRot-3b = black curve CoRot-3b = red curves

No stellar irradiation

Half-sphere redistribution

Main actors of exoplanet’s field

Main actors of exoplanet’s field

authors geometry opacities chemistry radiative transfer

Barman et al. ‘01, ‘05, ‘06Barman ‘08

1D, hydrostaticGlobal 3D reconstruction

Gas + dust CE, NLTE, Photo-ionization

Spherical symmetry, ALI

Sudarsky etal. ‘03,‘05,‘06Burrows etal.‘03,’04,’05,’06

1D, hydrostatic Gas + dust CE Plan-parallel, ALI

Seager et al. ‘98, ‘00, ‘05 1D, hydrostatic Gas + dust CE Plan-parallel (Feautrier)

Fortney et al. ‘05, ‘06 1D, hydrostatic Gas + dust CE by table interpolation

Plan-parallel, two-stream, NO scattering

Brown ‘01, Tinetti et al. ‘08

Ray tracing, hydrostatic Ad-hoc rotation

Gas + dust CE, Photo-ionizationPhotochemistry

Goukenleuque et al. ‘00, Iro et al. ‘05

1D, time relaxation, Ad-hoc rotation, Global 3D reconstruction

Gas + dust CE not updated with time

Plan-parallel, two-stream, WITH scattering

Freytag et al. ‘09 Local 3D Hydrodynamics, winds Gas + dust CE 3D (Feautrier)

Showman & Guillot ‘02 Local 3D hydrodynamics, winds - - Radiative gradient from RT models

Dobbs-Dixon & Lin ‘07 Global 3D hydrodynamics, rotation

Dust only CE Diffusion approximation

Cho et al. ‘96, ‘01, ‘03, ‘07Menou ‘03

Global 2D (single layered) hydrodynamics, rotation

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