Update 3/7

Read Murray-Clay paper: Authors seek to numerically determine validity of hypothesis that hot Jupiters could be evaporated down to their rocky cores over the planetary lifetime. They use a one-dimensional model that includes heating/cooling terms, tidal gravity, and the effects of ionization on the mass-loss rate, and ignore the Coriolis force. Numerically, they use a relaxation solver, and find solutions iteratively by removing simplifying conditions one at a time.

They find that, for main-sequence stars, about 20% of H is still neutral at the sonic point, and place an upper bound of ~3.3*1010 g/s on the mass loss rate. For hotter (T Tauri) stars, they find an upper bound of ~6.4*1012 g/s. The assumption of a hydrodynamic wind is shown to be self-consistent, and they estimate that these are overestimates by ~4x. By reducing the wind speed to subsonic values and including a stellar wind, the day-side wind may be reduced or completely suppressed - they hypothesize that this may lead to night-side outflows.

They compare observations to estimates from their model, and note a few possible reasons for the disagreement in Lyman-alpha lines. A promising candidate is cited as acceleration of neutral hydrogen due to charge exchange. They note that modelled spectrally-unresolved measurements appear to be in agreement with observation.

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