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Friends of Hot Jupiters. I. A Radial Velocity Search for Massive, Long-Period Companions to Close-In Gas Giant Planets

Knutson, Heather A. and Fulton, Benjamin J. and Montet, Benjamin T. and Kao, Melodie and Ngo, Henry and Howard, Andrew W. and Crepp, Justin R. and Hinkley, Sasha and Bakos, Gáspár Á. and Batygin, Konstantin and Johnson, John Asher and Morton, Timothy D. and Muirhead, Philip S. (2014) Friends of Hot Jupiters. I. A Radial Velocity Search for Massive, Long-Period Companions to Close-In Gas Giant Planets. Astrophysical Journal, 785 (2). Art. No. 126. ISSN 0004-637X.

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In this paper we search for distant massive companions to known transiting hot Jupiters that may have influenced the dynamical evolution of these systems. We present new radial velocity observations for a sample of 51 hot Jupiters obtained using the Keck HIRES instrument, and use these observations to search for long-term radial velocity accelerations. We find new, statistically significant accelerations in seven systems, including: HAT-P-10, HAT-P-20, HAT-P-22, HAT-P-29, HAT-P-32, WASP-10, and XO-2. We combine our radial velocity fits with Keck NIRC2 AO imaging data to place constraints on the allowed masses and orbital periods of the companions. The estimated masses of the companions range between 1-500 M_(Jup), with orbital semi-major axes typically between 1-75 AU. A significant majority of the companions detected by our survey are constrained to have minimum masses comparable to or larger than those of the short-period hot Jupiters in these systems, making them candidates for influencing the orbital evolution of the inner hot Jupiters. They also appear to occur preferentially in systems with more metal-rich host stars, and with typical orbital separations that are larger than those of multi-planet systems without hot Jupiters. We estimate a total occurrence rate of 55% +11% / -10% for companions with masses between 1-13 M_(Jup) and orbital semi-major axes between 1-20 AU in our sample. We find no statistically significant difference between the frequency of companions in hot Jupiter systems with misaligned or eccentric orbits and those with well-aligned, circular orbits. We combine our expanded sample of radial velocity measurements with constraints from transit and secondary eclipse observations to provide improved measurements of the physical and orbital characteristics of all of the hot Jupiters included in our survey.

Item Type:Article
Related URLs:
URLURL TypeDescription Paper
Knutson, Heather A.0000-0002-0822-3095
Fulton, Benjamin J.0000-0003-3504-5316
Montet, Benjamin T.0000-0001-7516-8308
Kao, Melodie0000-0001-5125-1414
Ngo, Henry0000-0001-5172-4859
Howard, Andrew W.0000-0001-8638-0320
Crepp, Justin R.0000-0003-0800-0593
Hinkley, Sasha0000-0001-8074-2562
Bakos, Gáspár Á.0000-0001-7204-6727
Batygin, Konstantin0000-0002-7094-7908
Johnson, John Asher0000-0001-9808-7172
Morton, Timothy D.0000-0002-8537-5711
Muirhead, Philip S.0000-0002-0638-8822
Alternate Title:Friends of Hot Jupiters I: A Radial Velocity Search for Massive, Long-Period Companions in Hot Jupiter Systems
Additional Information:© 2014 American Astronomical Society. Received 2013 December 3; accepted 2014 March 11; published 2014 April 3. We thank Jason Wright and Joshua Winn for their thoughtful input on early drafts of this paper. This work was based on observations at the W. M. Keck Observa tory granted by the University of Hawaii, the University of California, and the California Institute of Technology. We thank the observers who contributed to the measure ments reported here and acknowledge the efforts of the Keck Observatory staff. We extend special thanks to those of Hawaiian ancestry on whose sacred mountain of Mauna Kea we are privileged to be guests. B.T.M. is supported by the National Science Foundation Graduate Research Fellowship under Grant No. DGE−1144469. J.A.J. and G.B. are supported by grants from the David and Lucille Packard Foundation and the Alfred P. Sloan Foundation. P.S.M. acknowledges support for this work from the Hubble Fellowship Program, provided by NASA through Hubble Fellowship grant HST-HF-51326.01-A awarded by the STScI, which is operated by the AURA, Inc., for NASA, under contract NAS 5-26555. S.H. is supported by an NSF Astronomy and Astrophysics Post- doctoral Fellowship under award AST-1203023. G.B. ac knowledges support from grant NSF AST-1108686. Facilities: Keck:I (HIRES), Keck:II (NIRC2)
Funding AgencyGrant Number
NSF Graduate Research FellowshipDGE-1144469
David and Lucile Packard FoundationUNSPECIFIED
Alfred P. Sloan FoundationUNSPECIFIED
NASA Hubble FellowshipHST-HF-51326.01-A
NASANAS 5-26555
NSF Astronomy and Astrophysics FellowshipAST-1203023
Subject Keywords:binaries: eclipsing — planetary systems — techniques: radial velocity, adaptive optics
Issue or Number:2
Record Number:CaltechAUTHORS:20131223-152510330
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Official Citation:Friends of Hot Jupiters. I. A Radial Velocity Search for Massive, Long-period Companions to Close-in Gas Giant Planets Heather A. Knutson et al. 2014 ApJ 785 126
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:43152
Deposited By: Ruth Sustaita
Deposited On:23 Dec 2013 23:47
Last Modified:09 Mar 2020 13:18

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