Searching for Rapid Orbital Decay of WASP-18b

  title={Searching for Rapid Orbital Decay of WASP-18b},
  author={Ashlee N. Wilkins and Laetitia Delrez and Adrian J. Barker and Drake L. Deming and Douglas P. Hamilton and Micha{\"e}l Gillon and Emmanuel Jehin},
  journal={The Astrophysical Journal Letters},
The WASP-18 system, with its massive and extremely close-in planet, WASP-18b (Mp = 10.3MJ, a = 0.02 au, P = 22.6 hr), is one of the best-known exoplanet laboratories to directly measure Q′, the modified tidal quality factor and proxy for efficiency of tidal dissipation, of the host star. Previous analysis predicted a rapid orbital decay of the planet toward its host star that should be measurable on the timescale of a few years, if the star is as dissipative as is inferred from the… 
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