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Two Exoplanets Discovered at Keck Observatory

Valenti, Jeff A. and Fischer, Debra and Marcy, Geoffrey W. and Johnson, John A. and Henry, Gregory W. and Wright, Jason T. and Howard, Andrew W. and Giguere, Matt and Isaacson, Howard (2009) Two Exoplanets Discovered at Keck Observatory. Astrophysical Journal, 702 (2). pp. 989-997. ISSN 0004-637X.

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We present two exoplanets detected at Keck Observatory. HD 179079 is a G5 subgiant that hosts a hot Neptune planet with M sin i = 27.5 M_⊕ in a 14.48 days, low-eccentricity orbit. The stellar reflex velocity induced by this planet has a semiamplitude of K = 6.6 m s^(–1). HD 73534 is a G5 subgiant with a Jupiter-like planet of M sin i = 1.1 M_(Jup) and K = 16 m s^(–1) in a nearly circular 4.85 yr orbit. Both stars are chromospherically inactive and metal-rich. We discuss a known, classical bias in measuring eccentricities for orbits with velocity semiamplitudes, K, comparable to the radial velocity uncertainties. For exoplanets with periods longer than 10 days, the observed exoplanet eccentricity distribution is nearly flat for large amplitude systems (K > 80 m s^(–1)), but rises linearly toward low eccentricity for lower amplitude systems (K > 20 m s^(–1)).

Item Type:Article
Related URLs:
URLURL TypeDescription
Valenti, Jeff A.0000-0003-3305-6281
Fischer, Debra0000-0003-2221-0861
Marcy, Geoffrey W.0000-0002-2909-0113
Johnson, John A.0000-0001-9808-7172
Henry, Gregory W.0000-0003-4155-8513
Wright, Jason T.0000-0001-6160-5888
Howard, Andrew W.0000-0001-8638-0320
Isaacson, Howard0000-0002-0531-1073
Additional Information:© 2009 American Astronomical Society. Received 2008 December 21; accepted 2009 July 7; published 2009 August 18. Based on observations obtained at the Keck Observatory, which is operated by the University of California. We gratefully acknowledge the dedication and support of the Keck Observatory staff, in particular Grant Hill for support with HIRES. D.A.F. acknowledges research support from NASA grant NNX08AF42G. G.W.H. acknowledges support from NASA, NSF, Tennessee State University, and the State of Tennessee through its Centers of Excellence program. We thank the NASA Exoplanet Science Institute (NExScI) for support through the KPDA program. We thank the NASA and NOAOTelescope assignment committees for allocations of telescope time. The authors extend thanks to those of Hawaiian ancestry on whose sacred mountain of Mauna Kea we are privileged to be guests. Without their kind hospitality, the Keck observations presented here would not have been possible. This research has made use of the SIMBAD database, operated at CDS, Strasbourg, France, and of NASA’s Astrophysics Data System Bibliographic Services.
Group:Infrared Processing and Analysis Center (IPAC)
Funding AgencyGrant Number
Tennessee State UniversityUNSPECIFIED
State of Tennessee Centers of Excellence programUNSPECIFIED
NASA Exoplanet Science Institute (NExScI)UNSPECIFIED
Subject Keywords:planetary systems; stars: individual (HD 179079, HD 143174, HD 73534)
Issue or Number:2
Record Number:CaltechAUTHORS:20130111-110711929
Persistent URL:
Official Citation:Two Exoplanets Discovered at Keck Observatory Jeff A. Valenti et al. 2009 ApJ 702 989
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:36323
Deposited By: Ruth Sustaita
Deposited On:11 Jan 2013 21:04
Last Modified:09 Mar 2020 13:19

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