Browsing by Subject "radial-velocity measurements"

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    The Pan-Pacific Planet Search. II. Confirmation Of A Two-Planet System Around Hd 121056
    (2015-02) Wittenmyer, Robert A.; Wang, Lifan; Liu, Fan; Horner, Jonathan; Endl, Michael; Johnson, John A.; Tinney, C. G.; Carter, B. D.; Endl, Michael
    Precise radial velocities from the Anglo-Australian Telescope (AAT) 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 M-Jup. These data also confirm the planetary nature of the outer companion, with m sin i = 3.9 +/- 0.6 M-Jup 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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    Retired A Stars and Their Companions. VII. 18 New Jovian Planets
    (2011-12) Johnson, J. Aasher; Clanton, Christian; Howard, Andrew W.; Bowler, Brendan P.; Henry, Gregory W.; Marcy, Geoffrey W.; Crepp, Justin R.; Endl, Michael; Cochran, William D.; MacQueen, Phillip J.; Wright, Jason T.; Isaacson, Howard; Endl, Michael; Cochran, William D.; MacQueen, Phillip J.
    We report the detection of 18 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 <= M(star)/M(circle dot) <= 1.95, radii 2.5 <= R(star)/R(circle dot) <= 8.7, and metallicities -0.46 <= [Fe/H] <= +0.30. The planets have minimum masses 0.9 M(Jup) <= M(P) sin i less than or similar to 13 M(Jup) and semimajor axes a >= 0.76 AU. These detections represent a 50% increase in the number of planets known to orbit stars more massive than 1.5M(circle dot) and provide valuable additional inFormation about the properties of planets around stars more massive than the Sun.