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arXiv · 1108.4205

Retired A Stars and Their Companions: Eighteen New Jovian Planets

John Asher Johnson·Christian Clanton·Andrew W. Howard·Brendan P. Bowler·Gregory W. Henry·Geoffrey W. Marcy·Justin R. Crepp·Michael Endl·William D. Cochran·Phillip J. MacQueen·Jason T. Wright·Howard Isaacson
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Abstract

We report the detection of eighteen Jovian planets discovered as part of our Doppler survey of subgiant stars at Keck Observatory, with follow-up Doppler and photometric observations made at McDonald and Fairborn Observatories, respectively. The host stars have masses 0.927 < Mstar /Msun < 1.95, radii 2.5 < Rstar/Rsun < 8.7, and metallicities -0.46 < [Fe/H] < +0.30. The planets have minimum masses 0.9 MJup < MP sin i <3 MJup and semima jor axes a > 0.76 AU. These detections represent a 50% increase in the number of planets known to orbit stars more massive than 1.5 Msun and provide valuable additional information about the properties of planets around stars more massive thantheSun.

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John Asher Johnson, Christian Clanton, Andrew W. Howard, Brendan P. Bowler, Gregory W. Henry, Geoffrey W. Marcy, Justin R. Crepp, Michael Endl, William D. Cochran, Phillip J. MacQueen, Jason T. Wright, Howard Isaacson. 2011-08-21. Retired A Stars and Their Companions: Eighteen New Jovian Planets. https://doi.org/10.1088/0067-0049/197/2/26

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