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A resonant chain of four transiting, sub-Neptune planets

Mills, Sean M. and Fabrycky, Daniel C. and Migaszewski, Cezary and Ford, Eric B. and Petigura, Erik and Isaacson, Howard (2016) A resonant chain of four transiting, sub-Neptune planets. Nature, 533 (7604). pp. 509-512. ISSN 0028-0836.

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[img] Plain Text (Supplementary Table Dataset 1, a tsv file of predicted transmit times for Kepler-223. Columns: [Transit_Number] \t [Time_(BJD-2454900)] \t [1-Sigma_Uncertainty_(d)]. ...) - Supplemental Material
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[img] Image (JPEG) (Extended Data Figure 2: Long-cadence light curve for each planet, broken down by quarter (Q)) - Supplemental Material
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[img] Image (JPEG) (Extended Data Figure 3: Laplace-angle librations detected by binning transits into quarters and assuming zero eccentricity) - Supplemental Material
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[img] Image (JPEG) (Extended Data Figure 5: Orbital-period ratios of librating and non-librating solutions fitted to data) - Supplemental Material
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[img] Image (JPEG) (Extended Data Table 1: Mean Kepler-223 quarterly TTVs) - Supplemental Material
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[img] Image (JPEG) (Extended Data Table 2: Complete Kepler-223 parameters) - Supplemental Material
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[img] Image (JPEG) (Extended Data Table 3: Best-fit Kepler-223 initial conditions) - Supplemental Material
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Surveys have revealed many multi-planet systems containing super-Earths and Neptunes in orbits of a few days to a few months. There is debate whether in situ assembly or inward migration is the dominant mechanism of the formation of such planetary systems. Simulations suggest that migration creates tightly packed systems with planets whose orbital periods may be expressed as ratios of small integers (resonances), often in a many-planet series (chain). In the hundreds of multi-planet systems of sub-Neptunes, more planet pairs are observed near resonances than would generally be expected, but no individual system has hitherto been identified that must have been formed by migration. Proximity to resonance enables the detection of planets perturbing each other. Here we report transit timing variations of the four planets in the Kepler-223 system, model these variations as resonant-angle librations, and compute the long-term stability of the resonant chain. The architecture of Kepler-223 is too finely tuned to have been formed by scattering, and our numerical simulations demonstrate that its properties are natural outcomes of the migration hypothesis. Similar systems could be destabilized by any of several mechanisms, contributing to the observed orbital-period distribution, where many planets are not in resonances. Planetesimal interactions in particular are thought to be responsible for establishing the current orbits of the four giant planets in the Solar System by disrupting a theoretical initial resonant chain similar to that observed in Kepler-223.

Item Type:Article
Related URLs:
URLURL TypeDescription ReadCube access data Paper
Mills, Sean M.0000-0002-4535-6241
Fabrycky, Daniel C.0000-0003-3750-0183
Ford, Eric B.0000-0001-6545-639X
Petigura, Erik0000-0003-0967-2893
Isaacson, Howard0000-0002-0531-1073
Additional Information:© 2016 Macmillan Publishers Limited. Received 07 August 2015; Accepted 11 February 2016; Published online 11 May 2016. We thank A. Howard and G. Marcy for their role in obtaining spectra, and E. Agol, J. Lissauer, and J. Bean for comments on the manuscript. This material is based on work supported by NASA under grant numbers NNX14AB87G (D.C.F.), NNX12AF73G (E.B.F.) and NNX14AN76G (E.B.F.) issued through the Kepler Participating Scientist Program. E.B.F. received support from NASA Exoplanet Research Program award NNX15AE21G. D.C.F. received support from the Alfred P. Sloan Foundation. C.M. was supported by the Polish National Science Centre MAESTRO grant DEC-2012/06/A/ST9/00276. Author Contributions: S.M.M. performed the photodynamic, stability, tidal dissipation and spectral evolution analyses and led the paper authorship. D.C.F. designed the study, performed TTV and Laplace-angle libration analysis, and assisted writing the paper. C.M. performed the migration analysis, assisted in initial data fitting and contributed to the writing of the paper. E.B.F. advised on the DEMCMC analysis and paper direction. E.P. and H.I. obtained and analysed the spectra. All authors read and edited the manuscript. The authors declare no competing financial interests.
Group:Infrared Processing and Analysis Center (IPAC)
Funding AgencyGrant Number
Alfred P. Sloan FoundationUNSPECIFIED
National Science Centre (Poland)DEC-2012/06/A/ST9/00276
Issue or Number:7604
Record Number:CaltechAUTHORS:20160512-073340318
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Official Citation:A resonant chain of four transiting, sub-Neptune planets Sean M. Mills, Daniel C. Fabrycky, Cezary Migaszewski, Eric B. Ford, Erik Petigura & Howard Isaacson Nature 533, 509–512 (26 May 2016) doi:10.1038/nature17445
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:67037
Deposited By: Tony Diaz
Deposited On:12 May 2016 21:06
Last Modified:21 Apr 2020 21:17

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