Improved parameters for the transiting planet HD 17156b: a high-density giant planet with a very eccentric orbit *,**
Observatoire de Genève, Université de Genève, 51 Chemin des Maillettes, 1290 Sauverny, Switzerland e-mail: firstname.lastname@example.org
2 Laboratoire d'Astrophysique, École Polytechnique Fédérale de Lausanne (EPFL), Observatoire de Sauverny, 1290 Versoix, Switzerland
Accepted: 12 April 2008
We report high-precision transit photometry for the recently detected planet HD 17156b. Using these new data with previously published transit photometry and radial velocity measurements, we perform a combined analysis based on a Markov Chain Monte Carlo approach. The resulting mass and radius RJup for the planet places it at the outer edge of the density distribution of known transiting planets with . The obtained transit ephemeris is BJD. The derived plausible tidal circularization time scales for HD 17156b are larger than the age of the host star. The measured high orbital eccentricity can thus not be interpreted as the clear sign of the presence of another body in the system.
Key words: binaries: eclipsing / planetary systems / stars: individual: HD 17156 / techniques: photometric
Based on observations made with the Mercator Telescope, operated on the island of La Palma by the Flemish Community, at the Spanish Observatorio del Roque de los Muchachos of the Instituto de Astrofísica de Canarias.
© ESO, 2008