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arXiv · 0907.5080

A Substellar Companion in a 1.3 yr Nearly-circular Orbit of HD 16760

Bunei Sato·Debra A. Fischer·Shigeru Ida·Hiroki Harakawa·Masashi Omiya·John A. Johnson·Geoffrey W. Marcy·Eri Toyota·Yasunori Hori·Howard Isaacson·Andrew W. Howard·Kathryn M. G. Peek
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Abstract

We report the detection of a substellar companion orbiting the G5 dwarf HD 16760 from the N2K sample. Precise Doppler measurements of the star from Subaru and Keck revealed a Keplerian velocity variation with a period of 466.47+-0.35 d, a semiamplitude of 407.71+-0.84 m/s, and an eccentricity of 0.084+-0.003. Adopting a stellar mass of 0.78+-0.05 M_Sun, we obtain a minimum mass for the companion of 13.13+-0.56 M_JUP, which is close to the planet/brown-dwarf transition, and the semimajor axis of 1.084+-0.023 AU. The nearly circular orbit despite the large mass and intermediate orbital period makes this companion unique among known substellar companions.

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Bunei Sato, Debra A. Fischer, Shigeru Ida, Hiroki Harakawa, Masashi Omiya, John A. Johnson, Geoffrey W. Marcy, Eri Toyota, Yasunori Hori, Howard Isaacson, Andrew W. Howard, Kathryn M. G. Peek. 2009-07-29. A Substellar Companion in a 1.3 yr Nearly-circular Orbit of HD 16760. https://doi.org/10.1088/0004-637x/703/1/671

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