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arXiv · 1412.6889

The Pan-Pacific Planet Search. II. Confirmation of a two-planet system around HD 121056

Robert A. Wittenmyer·Liang Wang·Fan Liu·Jonathan Horner·Michael Endl·John Asher Johnson·C. G. Tinney·B. D. Carter
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Abstract

Precise radial velocities from the Anglo-Australian Telescope confirm the presence of a rare short-period planet around the K0 giant HD 121056. An independent two-planet solution using the AAT data shows that the inner planet has P=89.1+/-0.1 days, and m sin i=1.35+/-0.17 Mjup. These data also confirm the planetary nature of the outer companion, with m sin i=3.9+/-0.6 Mjup and a=2.96+/-0.16 AU. HD 121056 is the most-evolved star to host a confirmed multiple-planet system, and is a valuable example of a giant star hosting both a short-period and a long-period planet.

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Robert A. Wittenmyer, Liang Wang, Fan Liu, Jonathan Horner, Michael Endl, John Asher Johnson, C. G. Tinney, B. D. Carter. 2014-12-22. The Pan-Pacific Planet Search. II. Confirmation of a two-planet system around HD 121056. https://doi.org/10.1088/0004-637x%2F800%2F1%2F74

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