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arXiv · 1011.0414

The NASA-UC Eta-Earth Program: III. A Super-Earth orbiting HD 97658 and a Neptune-mass planet orbiting Gl 785

Andrew W. Howard·John Asher Johnson·Geoffrey W. Marcy·Debra A. Fischer·Jason T. Wright·Gregory W. Henry·Howard Isaacson·Jeff A. Valenti·Jay Anderson·Nikolai E. Piskunov
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Abstract

We report the discovery of planets orbiting two bright, nearby early K dwarf stars, HD 97658 and Gl 785. These planets were detected by Keplerian modelling of radial velocities measured with Keck-HIRES for the NASA-UC Eta-Earth Survey. HD 97658 b is a close-in super-Earth with minimum mass Msini = 8.2 +/- 1.2 M_Earth, orbital period P = 9.494 +/- 0.005 d, and an orbit that is consistent with circular. Gl 785 b is a Neptune-mass planet with Msini = 21.6 +/- 2.0 M_Earth, P = 74.39 +/- 0.12 d, and orbital eccentricity 0.30 +/- 0.09. Photometric observations with the T12 0.8 m automatic photometric telescope at Fairborn Observatory show that HD 97658 is photometrically constant at the radial velocity period to 0.09 mmag, supporting the existence of the planet.

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Andrew W. Howard, John Asher Johnson, Geoffrey W. Marcy, Debra A. Fischer, Jason T. Wright, Gregory W. Henry, Howard Isaacson, Jeff A. Valenti, Jay Anderson, Nikolai E. Piskunov. 2010-11-01. The NASA-UC Eta-Earth Program: III. A Super-Earth orbiting HD 97658 and a Neptune-mass planet orbiting Gl 785. https://doi.org/10.1088/0004-637x%2F730%2F1%2F10

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