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arXiv · 0807.1318

A Precise Estimate of the Radius of HD 149026b

Philip Nutzman·David Charbonneau·Joshua N. Winn·Heather A. Knutson·Jonathan J. Fortney·Matthew J. Holman·Eric Agol
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Abstract

We present Spitzer 8 micron transit observations of the extrasolar planet system HD 149026. At this wavelength, transit light curves are weakly affected by stellar limb-darkening, allowing for a simpler and more accurate determination of planetary parameters. We measure a planet-star radius ratio of R_p/R_s = 0.05158 +/- 0.00077, and in combination with ground-based data and independent constraints on the stellar mass and radius, we derive an orbital inclination of i = 85.4 +0.9/-0.8 deg. and a planet radius of 0.755 +/- 0.040 Jupiter radii. These measurements further support models in which the planet is greatly enriched in heavy elements.

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Philip Nutzman, David Charbonneau, Joshua N. Winn, Heather A. Knutson, Jonathan J. Fortney, Matthew J. Holman, Eric Agol. 2008-07-08. A Precise Estimate of the Radius of HD 149026b. https://doi.org/10.1017/s1743921308026951

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