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arXiv · 0806.4008

HAT-P-9b: A Low Density Planet Transiting a Moderately Faint F star

Avi Shporer·Gaspar A. Bakos·Francois Bouchy·Frederic Pont·Geza Kovacs·Dave W. Latham·Brigitta Sipocz·Guillermo Torres·Tsevi Mazeh·Gilbert A. Esquerdo·Andras Pal·Robert W. Noyes·Dimitar D. Sasselov·Jozsef Lazar·Istvan Papp·Pal Sari·Gabor Kovacs
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Abstract

We report the discovery of a planet transiting a moderately faint (V=12.3 mag) late F star, with an orbital period of 3.92289 +/- 0.00004 days. From the transit light curve and radial velocity measurements we determine that the radius of the planet is R_p = 1.40 +/- 0.06 R_Jup and that the mass is M_p = 0.78 +/- 0.09 M_Jup. The density of the new planet, rho = 0.35 +/- 0.06 g cm^{-3}, fits to the low-density tail of the currently known transiting planets. We find that the center of transit is at T_c = 2454417.9077 +/- 0.0003 (HJD), and the total transit duration is 0.143 +/- 0.004 days. The host star has M_s = 1.28 +/- 0.13 M_Sun and R_s = 1.32 +/- 0.07 R_Sun.

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Avi Shporer, Gaspar A. Bakos, Francois Bouchy, Frederic Pont, Geza Kovacs, Dave W. Latham, Brigitta Sipocz, Guillermo Torres, Tsevi Mazeh, Gilbert A. Esquerdo, Andras Pal, Robert W. Noyes, Dimitar D. Sasselov, Jozsef Lazar, Istvan Papp, Pal Sari, Gabor Kovacs. 2008-06-25. HAT-P-9b: A Low Density Planet Transiting a Moderately Faint F star. https://doi.org/10.1088/0004-637x/690/2/1393

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