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Stone-Proga paper

Paper is a comparison of 2D simulations (of close-in hot Jupiters) to spherically symmetric simulations run by others. They characterize escape from the planet with the hydrodynamic escape parameter (lambda), ratio of gravitational potential to thermal potential - a small lambda suggests a thermal wind. They use no magnetism (hydrodynamic rather than MHD), and ignore heating and small-scale effects at the base of the wind. The wind is made self-consistent by fixing the density and energy at the base.

In models with no stellar wind and an isothermal outflow, they find that the sonic surface of the wind is closer to the planet, with a slower radial velocity on the night side of the planet, and a very evident shock in the |v|/v_s plot at various angles. For larger values of gamma, this shock produces a delta T, and the sonic surface is farther from the planet (but still nearer than in the spherically symmetric models). Introducing a stellar wind creates a back-swept profile, but has little effect on the sonic surfaces or mass-loss rate.

Experimenting with AstroBEAR

Ran OutflowWind simulations with varying parameters. Thickness and wind velocity don't appear to have any effect - perhaps an effect of rescaling? Velocity speeds up the simulation as a whole. The rest are as follows:

Reference (default parameters, 100 frames, 2 units computational time (conversion?)):

Radius increases size of wind, but otherwise has little effect, at least at small values (expected).

Radius of 2:

Increasing density appears to decrease relative density at the center of the front of the outflow (slightly counter-intuitive, but makes sense).

Density of 5: Density of 10: Density of 20:

Increasing temp. creates a more diffuse cloud at the end (predictably). Temp = 0 appears to cause buggy behavior.

Temp = 0: Temp = 1: Temp = 5:

Also tried a run at 1000 frames, but definitely overkill for time.