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arXiv · 0705.0935

A Planetary Mass Companion to the K0 Giant HD 17092

A. Niedzielski·M. Konacki·A. Wolszczan·G. Nowak·G. Maciejewski·R. C. Gelino·M. Shao·M. Shetrone·L. W. Ramsey
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Abstract

We report the discovery of a substellar-mass companion to the K0-giant HD 17092 with the Hobby-Eberly Telescope. In the absence of any correlation of the observed 360-day periodicity with the standard indicators of stellar activity, the observed radial velocity variations are most plausibly explained in terms of a Keplerian motion of a planetary-mass body around the star. With the estimated stellar mass of 2.3Msun, the minimum mass of the planet is 4.6MJ. The planet's orbit is characterized by a mild eccentricity of e=0.17 and a semi-major axis of 1.3 AU. This is the tenth published detection of a planetary companion around a red giant star. Such discoveries add to our understanding of planet formation around intermediate-mass stars and they provide dynamical information on the evolution of planetary systems around post-main sequence stars.

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A. Niedzielski, M. Konacki, A. Wolszczan, G. Nowak, G. Maciejewski, R. C. Gelino, M. Shao, M. Shetrone, L. W. Ramsey. 2007-05-07. A Planetary Mass Companion to the K0 Giant HD 17092. https://doi.org/10.1086/521784

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