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Planetary Atmospheres

Description of Problem

Hot Jupiters receive much more energy through stellar irradiation then internal heating. They are also tidally locked due to their proximity. Dayside at 1000K, night side at 100K without heat redistribution.

What frame to choose?

• Rotating about center of mass of system
• Rotating about axis of secondary
• Non rotating

Dobbs Dixon '08 Domain

• Radius goes from 7.95e9 cm to 8.65e9 cm (1.06 -1.2 R_j)
• Single Temperature (assumes Planck opacity is >> )
• They use \lambda = \frac{2+R}{6+3R+R^2} instead of \frac{1}{R}\left ( \coth{R}-\frac{1}{R} \right )

• \gamma=7/5
• \chi=2.3
• Roseland opacities found using Pollack et al 1985 for low T with Alexander & Ferguson for high T
• Initial Density and Temperature profiles taken from 1D model (B1 of Bodenheimer 2001) (.63 M_J for 4.5 Gyr with a 1200 degree outer boundary)
• Outer boundary set to T= max(1200 K * [cos(phi)*cos(theta)]^{(¼), 100 K)}

• Non rotating model - no coriolis or centrifugal forces… - no winds
• Rotating model - 3 days

Dobbs Dixon'10

• Added viscosity
• Added stellar heating using optical depth and high energy planck opacity

Current differences between Ian's code and AstroBEAR

• AstroBEAR folds in gas/radiation energy coupling into implicit solve… Hypre has both kappa_R and kappa_P terms - with sub-cycling for changes in source function.
• AstroBEAR also assumes 'kappa' is constant over implicit update… assumes \frac{\partial \kappa}{\partial T} = 0…
• No Kappa_A terms (stellar heating) in AstroBEAR
• Need to develop communication patterns for calculating optical depth from star to get heating term correct. Could use initial spherical profile to estimate optical depth as a function of position? Not sure how this is done in Ian's code
• Viscosity may need to be incorporated later… Shule is developing this.

• Second AMR implicit solve may need to be added later (ie Howell and Greenough 2002)

Initial Params

• Density Profile
• Planet modeled as point particle or self gravity?
• Gravity from primary important?