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HAT-P-17b,c: A Transiting, Eccentric, Hot Saturn and a Long-period, Cold Jupiter

Howard, A. W. and Bakos, G. Á. and Hartman, J. and Torres, G. and Shporer, A. and Mazeh, T. and Kovács, Géza and Latham, D. W. and Noyes, R. W. and Fischer, D. A. and Johnson, J. A. and Marcy, G. W. and Esquerdo, G. A. and Béky, B. and Butler, R. P. and Sasselov, D. D. and Stefanik, R. P. and Perumpilly, G. and Lázár, J. and Papp, I. and Sári, P. (2012) HAT-P-17b,c: A Transiting, Eccentric, Hot Saturn and a Long-period, Cold Jupiter. Astrophysical Journal, 749 (2). Art. No. 134. ISSN 0004-637X.

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We report the discovery of HAT-P-17b,c, a multi-planet system with an inner transiting planet in a short-period, eccentric orbit and an outer planet in a 4.4 yr, nearly circular orbit. The inner planet, HAT-P-17b, transits the bright V = 10.54 early K dwarf star GSC 2717-00417, with an orbital period P = 10.338523 ± 0.000009 days, orbital eccentricity e = 0.342 ± 0.006, transit epoch T_c = 2454801.16943 ± 0.00020 (BJD: barycentric Julian dates throughout the paper are calculated from Coordinated Universal Time (UTC)), and transit duration 0.1690 ± 0.0009 days. HAT-P-17b has a mass of 0.534 ± 0.018 M_J and radius of 1.010 ± 0.029 R_J yielding a mean density of 0.64 ± 0.05 g cm^(–3). This planet has a relatively low equilibrium temperature in the range 780-927 K, making it an attractive target for follow-up spectroscopic studies. The outer planet, HAT-P-17c, has a significantly longer orbital period P_2 = 1610 ± 20 days and a minimum mass m_2sini_2 = 1.31^(+0.18)_(–0.15) M_J. The orbital inclination of HAT-P-17c is unknown as transits have not been observed and may not be present. The host star has a mass of 0.86 ± 0.04 M_☉, radius of 0.84 ± 0.02 R_☉, effective temperature 5246 ± 80 K, and metallicity [Fe/H] = 0.00 ± 0.08. HAT-P-17 is the second multi-planet system detected from ground-based transit surveys.

Item Type:Article
Related URLs:
URLURL TypeDescription
Howard, A. W.0000-0001-8638-0320
Bakos, G. Á.0000-0001-7204-6727
Torres, G.0000-0002-5286-0251
Shporer, A.0000-0002-1836-3120
Latham, D. W.0000-0001-9911-7388
Fischer, D. A.0000-0003-2221-0861
Johnson, J. A.0000-0001-9808-7172
Marcy, G. W.0000-0002-2909-0113
Esquerdo, G. A.0000-0002-9789-5474
Sasselov, D. D.0000-0001-7014-1771
Additional Information:© 2012 American Astronomical Society. Received 2010 August 24; accepted 2011 August 23; published 2012 April 2. Based in part on observations obtained at the W. M. Keck Observatory, which is operated by the University of California and the California Institute of Technology. Keck time has been granted by NOAO and NASA. We thank E. Agol, H. Knutson, J. Winn, and J. Wright for helpful conversations. HATNet operations have been funded by NASA grants NNG04GN74G, NNX08AF23G, and SAO IR&D grants. A.W.H. gratefully acknowledges support from a Townes Post-doctoral Fellowship at the U. C. Berkeley Space Sciences Laboratory. Work of G. Á. B. and J. Johnson were supported by the Postdoctoral Fellowship of the NSF Astronomy and Astrophysics Program (AST-0702843 and AST-0702821, respectively). G.T. acknowledges partial support from NASA grant NNX09AF59G. We acknowledge partial support also from the Kepler mission under NASA Cooperative Agreement NCC2-1390 (D.W.L.: PI). G.K. thanks the Hungarian Scientific Research Foundation (OTKA) for support through grant K-81373. T.M. acknowledges the Israel Science Foundation (grant 655/07). This research has made use of Keck telescope time granted through NOAO and NASA. We thank Ezra Mashal for his help in operating the Wise-HAT telescope over the past years. We thank the TLC project (M. Holman and J. Winn) for swapping time on the 1.2 m telescope at short notice. This research has made use of the Exoplanet Orbit Database and the Exoplanet Data Explorer at, the SIMBAD database (operated at CDS, Strasbourg, France), and NASA’s Astrophysics Data System Bibliographic Services. Finally, the authors wish to extend special thanks to those of Hawaiian ancestry on whose sacred mountain of Mauna Kea we were privileged to be guests. Without their generous hospitality, the Keck observations presented herein would not have been possible.
Funding AgencyGrant Number
Smithsonian Astrophysical ObservatoryUNSPECIFIED
UC Berkeley Space Sciences Laboratory Townes FellowshipUNSPECIFIED
NSF Astronomy and Astrophysics FellowshipAST-0702843
NSF Astronomy and Astrophysics FellowshipAST-0702821
Hungarian Scientific Research Foundation (OTKA)K-81373
Israel Science Foundation655/07
National Optical Astronomy Observatory (NOAO)UNSPECIFIED
Subject Keywords:planetary systems; stars: individual (HAT-P-17, GSC 2717-00417); techniques: photometric; techniques: spectroscopic
Issue or Number:2
Record Number:CaltechAUTHORS:20120515-143255518
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Official Citation:HAT-P-17b,c: A Transiting, Eccentric, Hot Saturn and a Long-period, Cold Jupiter A. W. Howard et al. 2012 ApJ 749 134
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:31477
Deposited By: Ruth Sustaita
Deposited On:15 May 2012 22:16
Last Modified:09 Mar 2020 13:19

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