Refined Parameters of the Planet Orbiting HD 189733
We report on the BVRI multiband follow-up photometry of the transiting extrasolar planet HD 189733b. We revise the transit parameters and find a planetary radius of R_P = 1.154 ± 0.033R_J and an inclination of i_P = 85º.79 ± 0º.24. The new density (~1 g cm^(-3)) is significantly higher than the former estimate (~0.75 g cm^(-3)); this shows that from the current sample of nine transiting planets, only HD 209458 (and possibly OGLE-10b) have anomalously large radii and low densities. We note that due to the proximity of its parent star, HD 189733b currently has one of the most precise radius determinations among extrasolar planets. We calculate new ephemerides, P = 2.218573 ± 0.000020 days and T_0 = 2453629.39420 ± 0.00024 (HJD), and estimate the timing offsets of the 11 distinct transits with respect to the predictions of a constant orbital period, which can be used to reveal the presence of additional planets in the system.
Additional Information© 2006 American Astronomical Society. Received 2006 March 8; accepted 2006 May 18. Part of this work was funded by NASA grant NNG04GN74G. Work by G. Á . B. was supported by NASA through grant HST-HF-01170.01-A (Hubble Fellowship). H. K. is supported by a National Science Foundation Graduate Research Fellowship. D. W. L. thanks the Kepler mission for support through NASA Cooperative Agreement NCC2-1390. A. P. wishes to acknowledge the hospitality of the Harvard-Smithsonian Center for Astrophysics, where part of this work has been carried out. Work of A. P. was also supported by Hungarian OTKA grant T-038437. Research of T. M. and A. S.was partially supported by the German-Israeli Foundation for Scientific Research and Development. This publication makes use of data products from the Two Micron All Sky Survey (2MASS). We thank M. Hicken and R. Kirshner for swapping nights on the FLWO 1.2 m telescope on short notice.
Published - 0004-637X_650_2_1160.pdf