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An Eccentric Hot Jupiter Orbiting the Subgiant HD 185269

John A. Johnson·Geoffrey W. Marcy·Debra A. Fischer·Gregory W. Henry·Jason T. Wright·Howard Isaacson·Chris McCarthy
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Abstract

We report the detection of a Jupiter-mass planet in a 6.838 day orbit around the 1.28 solar mass subgiant HD 185269. The eccentricity of HD 185269b (e = 0.30) is unusually large compared to other planets within 0.1 AU of their stars. Photometric observations demonstrate that the star is constant to +/-0.0001 mag on the radial velocity period, strengthening our interpretation of a planetary companion. This planet was detected as part of our radial velocity survey of evolved stars located on the subgiant branch of the H-R diagram--also known as the Hertzsprung Gap. These stars, which have masses between 1.2 and 2.5 solar masses, play an important role in the investigation of the frequency of extrasolar planets as a function of stellar mass.

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John A. Johnson, Geoffrey W. Marcy, Debra A. Fischer, Gregory W. Henry, Jason T. Wright, Howard Isaacson, Chris McCarthy. 2006-11-09. An Eccentric Hot Jupiter Orbiting the Subgiant HD 185269. https://doi.org/10.1086/508255

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