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The Occurrence and Mass Distribution of Close-in Super-Earths, Neptunes, and Jupiters

Howard, Andrew W. and Marcy, Geoffrey W. and Johnson, John Asher and Fischer, Debra A. and Wright, Jason T. and Isaacson, Howard and Valenti, Jeff A. and Anderson, Jay and Lin, Doug N. C. and Ida, Shigeru (2010) The Occurrence and Mass Distribution of Close-in Super-Earths, Neptunes, and Jupiters. Science, 330 (6004). pp. 653-655. ISSN 0036-8075.

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The questions of how planets form and how common Earth-like planets are can be addressed by measuring the distribution of exoplanet masses and orbital periods. We report the occurrence rate of close-in planets (with orbital periods less than 50 days), based on precise Doppler measurements of 166 Sun-like stars. We measured increasing planet occurrence with decreasing planet mass (M). Extrapolation of a power-law mass distribution fitted to our measurements, df/dlogM = 0.39 M^(−0.48), predicts that 23% of stars harbor a close-in Earth-mass planet (ranging from 0.5 to 2.0 Earth masses). Theoretical models of planet formation predict a deficit of planets in the domain from 5 to 30 Earth masses and with orbital periods less than 50 days. This region of parameter space is in fact well populated, implying that such models need substantial revision.

Item Type:Article
Related URLs:
URLURL TypeDescription DOIArticle Paper
Howard, Andrew W.0000-0001-8638-0320
Marcy, Geoffrey W.0000-0002-2909-0113
Johnson, John Asher0000-0001-9808-7172
Fischer, Debra A.0000-0003-2221-0861
Wright, Jason T.0000-0001-6160-5888
Isaacson, Howard0000-0002-0531-1073
Valenti, Jeff A.0000-0003-3305-6281
Lin, Doug N. C.0000-0001-5466-4628
Additional Information:© 2010 American Association for the Advancement of Science. Received 8 July 2010; accepted 27 September 2010. This work was based on observations at the W. M. Keck Observatory granted by NASA and the University of California (UC). We thank the many observers who contributed to the measurements reported here and acknowledge the efforts and dedication of the Keck Observatory staff, especially S. Dahm, H. Tran, and G. Hill for support of HIRES and G. Wirth for support of remote observing. We acknowledge R. P. Butler and S. Vogt for many years of contributing to the data presented here. A.H. acknowledges support from a Townes Postdoctoral Fellowship at the UC Berkeley Space Sciences Laboratory. G.M. acknowledges NASA grant NNX06AH52G. Finally, we extend special thanks to those of Hawai`ian ancestry on whose sacred mountain of Mauna Kea we are privileged to be guests.
Funding AgencyGrant Number
UC Berkeley Space Sciences LaboratoryUNSPECIFIED
Issue or Number:6004
Record Number:CaltechAUTHORS:20101124-083910202
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Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:21011
Deposited By: Tony Diaz
Deposited On:24 Nov 2010 18:54
Last Modified:09 Mar 2020 13:19

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