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arXiv · 0712.2073

Improved parameters for the transiting planet HD 17156b: a high-density giant planet with a very eccentric orbit

M. Gillon·A. H. M. J. Triaud·M. Mayor·D. Queloz·S. Udry·P. North
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Abstract

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 M_p = 3.09 (+0.22-0.17) M_Jup and radius R_p = 1.23 (+0.17-0.20) R_Jup for the planet places it at the outer edge of the density distribution of known transiting planets with rho_p = 1.66 (+1.37-0.60) rho_Jup. The obtained transit ephemeris is T_tr = 2454438.48271 (+0.00077-0.00057) + N x 21.21747 (+0.00070-0.00067) 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 e = 0.6719 (+0.0052-0.0063) can thus not be interpreted as the clear sign of the presence of another body in the system.

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M. Gillon, A. H. M. J. Triaud, M. Mayor, D. Queloz, S. Udry, P. North. 2008-05-06. Improved parameters for the transiting planet HD 17156b: a high-density giant planet with a very eccentric orbit. https://doi.org/10.1051/0004-6361:20079238

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