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The Transit Light Curve Project. V. System Parameters and Stellar Rotation Period of HD 189733

Joshua N. Winn·Matthew J. Holman·Gregory W. Henry·Anna Roussanova·Keigo Enya·Yuzuru Yoshii·Avi Shporer·Tsevi Mazeh·John A. Johnson·Norio Narita·Yasushi Suto
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Abstract

We present photometry of HD 189733 during eight transits of its close-in giant planet, and out-of-transit photometry spanning two years. Using the transit photometry, we determine the stellar and planetary radii and the photometric ephemeris. Outside of transits, there are quasiperiodic flux variations with a 13.4 day period that we attribute to stellar rotation. In combination with previous results, we derive upper limits on the orbital eccentricity, and on the true angle between the stellar rotation axis and planetary orbit (as opposed to the angle between the projections of those axes on the sky).

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Joshua N. Winn, Matthew J. Holman, Gregory W. Henry, Anna Roussanova, Keigo Enya, Yuzuru Yoshii, Avi Shporer, Tsevi Mazeh, John A. Johnson, Norio Narita, Yasushi Suto. 2006-12-28. The Transit Light Curve Project. V. System Parameters and Stellar Rotation Period of HD 189733. https://doi.org/10.1086/512159

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