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arXiv · 1004.1779

Detection of a low-eccentricity and super-massive planet to the subgiant HD 38801

Hiroki Harakawa·Bun'ei Sato·Debra A. Fischer·Shigeru Ida·Masashi Omiya·John A. Johnson·Geoffrey W. Marcy·Eri Toyota·Yasunori Hori·Andrew W. Howard
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Abstract

We report the detection of a large mass planet orbiting around the K0 metal-rich subgiant HD38801 ($V=8.26$) by precise radial velocity (RV) measurements from the Subaru Telescope and the Keck Telescope. The star has a mass of $1.36M_{\odot}$ and metallicity of [Fe/H]= +0.26. The RV variations are consistent with a circular orbit with a period of 696.0 days and a velocity semiamplitude of 200.0\mps, which yield a minimum-mass for the companion of $10.7\mjup$ and semimajor axis of 1.71 AU. Such super-massive objects with very low-eccentricities and hundreds of days period are uncommon among the ensemble of known exoplanets.

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Hiroki Harakawa, Bun'ei Sato, Debra A. Fischer, Shigeru Ida, Masashi Omiya, John A. Johnson, Geoffrey W. Marcy, Eri Toyota, Yasunori Hori, Andrew W. Howard. 2010-04-11. Detection of a low-eccentricity and super-massive planet to the subgiant HD 38801. https://doi.org/10.1088/0004-637x%2F715%2F1%2F550

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