Planetary evaporation by UV and X‐ray radiation: basic hydrodynamics

  title={Planetary evaporation by UV and X‐ray radiation: basic hydrodynamics},
  author={James E. Owen and Alan P. Jackson},
  journal={Monthly Notices of the Royal Astronomical Society},
  • J. Owen, A. Jackson
  • Published 11 June 2012
  • Physics, Geology
  • Monthly Notices of the Royal Astronomical Society
We consider the evaporation of close-in planets by the star's intrinsic extreme-ultraviolet (EUV) and X-ray radiation. We calculate evaporation rates by solving the hydrodynamical problem for planetary evaporation including heating from both X-ray and EUV radiation. We show that most close-in planets (a < 0.1 au) are evaporating hydrodynamically, with the evaporation occurring in two distinct regimes: X-ray driven, in which the X-ray heated flow contains a sonic point, and EUV driven, in which… 
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