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Determination of stellar, orbital and planetary parameters using complete Monte-Carlo analysis -- the case of HAT-P-7b

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 نشر من قبل Andras Pal Mr.
 تاريخ النشر 2008
  مجال البحث فيزياء
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 تأليف Andras Pal




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The recently discovered transiting very hot Jupiter, HAT-P-7b, a planet detected by the telescopes of HATNet, turned out to be among the ones subjected to the highest irradiation from the parent star. As known, the combination of photometric and spectroscopic data for such an object yields the stellar, orbital and planetary parameters. In order to best characterize this particular planet, we carried out a complex analysis based on a complete and simultaneous Monte-Carlo solution using all available data. We included the discovery light curves, partial follow-up light curves, the radial velocity data, and we used the stellar evolution models to infer the stellar properties. This self-consistent way of modeling provides the most precise estimate of the a posteriori distributions of all of the system parameters of interest, and avoids making assumptions on the values and uncertainties of any of the internally derived variables describing the system. This analysis demonstrates that even partial light curve information can be valuable. This may become very important for future discoveries of planets with longer periods -- and therefore longer transit durations -- where the chance of observing a full event is small.



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379 - Andras Pal 2009
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