The Kepler-19 System: A Thick-envelope Super-Earth with Two Neptune-mass Companions Characterized Using Radial Velocities and Transit Timing Variations
- Creators
- Malavolta, Luca
- Dressing, Courtney D.
Abstract
We report a detailed characterization of the Kepler-19 system. This star was previously known to host a transiting planet with a period of 9.29 days, a radius of 2.2 R_⊕, and an upper limit on the mass of 20 M_⊕. The presence of a second, non-transiting planet was inferred from the transit time variations (TTVs) of Kepler-19b over eight quarters of Kepler photometry, although neither the mass nor period could be determined. By combining new TTVs measurements from all the Kepler quarters and 91 high-precision radial velocities obtained with the HARPS-N spectrograph, using dynamical simulations we obtained a mass of 8.4 ± 1.6 M ⊕ for Kepler-19b. From the same data, assuming system coplanarity, we determined an orbital period of 28.7 days and a mass of 13.1 ± 2.7 M_⊕ for Kepler-19c and discovered a Neptune-like planet with a mass of 20.3 ± 3.4 M_⊕ on a 63-day orbit. By comparing dynamical simulations with non-interacting Keplerian orbits, we concluded that neglecting interactions between planets may lead to systematic errors that can hamper the precision in the orbital parameters when the data set spans several years. With a density of 4.32 ± 0.87 g cm^(−3) (0.78 ± 0.16 ρ_⊕) Kepler-19b belongs to the group of planets with a rocky core and a significant fraction of volatiles, in opposition to low-density planets characterized only by transit time variations and an increasing number of rocky planets with Earth-like density. Kepler-19 joins the small number of systems that reconcile transit timing variation and radial velocity measurements.
Additional Information
© 2017 American Astronomical Society. Received 2016 September 14. Accepted 2017 March 20. Published 2017 April 24. We thank the anonymous referee for the prompt and careful review and for providing detailed and useful suggestions. The HARPS-N project was funded by the Prodex Program of the Swiss Space Office (SSO), the Harvard University Origin of Life Initiative (HUOLI), the Scottish Universities Physics Alliance (SUPA), the University of Geneva, the Smithsonian Astrophysical Observatory (SAO), the Italian National Astrophysical Institute (INAF), University of St. Andrews, Queen's University Belfast, and University of Edinburgh. The research leading to these results received funding from the European Union Seventh Framework Programme (FP7/2007-2013) under grant agreement number 313014 (ETAEARTH). This work was performed in part under contract with the California Institute of Technology/Jet Propulsion Laboratory funded by NASA through the Sagan Fellowship Program executed by the NASA Exoplanet Science Institute. A.V. is supported by the NSF Graduate Research Fellowship, grant No. DGE 1144152. This publication was made possible by a grant from the John Templeton Foundation. The opinions expressed in this publication are those of the authors and do not necessarily reflect the views of the John Templeton Foundation. This material is based upon work supported by NASA under grant No. NNX15AC90G issued through the Exoplanets Research Program. P.F. acknowledges support by Fundação para a Ciência e a Tecnologia (FCT) through Investigador FCT contract of reference IF/01037/2013 and POPH/FSE (EC) by FEDER funding through the program "Programa Operacional de Factores de Competitividade—COMPETE", and further support in the form of an exploratory project of reference IF/01037/2013CP1191/CT0001. X.D. is grateful to the Society in Science–Branco Weiss Fellowship for its financial support.Attached Files
Published - Malavolta_2017_AJ_153_224.pdf
Submitted - 1703.06885.pdf
Files
Name | Size | Download all |
---|---|---|
md5:dd96d75d4fa435030614ca23c93c0f6f
|
2.5 MB | Preview Download |
md5:5976a5f89ab2a3296176e0ade600f7c4
|
3.1 MB | Preview Download |
Additional details
- Eprint ID
- 76821
- Resolver ID
- CaltechAUTHORS:20170421-133315102
- Swiss Space Office (SSO)
- Harvard University
- Scottish Universities Physics Alliance
- University of Geneva
- Smithsonian Astrophysical Observatory
- Istituto Nazionale di Astrofisica (INAF)
- University of St. Andrews
- 313014 (ETAEARTH)
- European Research Council (ERC)
- NASA/JPL/Caltech
- DGE-1144152
- NSF Graduate Research Fellowship
- John Templeton Foundation
- NNX15AC90G
- NASA
- IF/01037/2013CP1191/CT0001
- Fundação para a Ciência e a Tecnologia (FCT)
- POPH/FSE (EC)
- POPH/FSE (EC)
- FEDER
- IF/01037/2013CP1191/CT0001
- Fundação para a Ciência e a Tecnologia (FCT)
- Society in Science–Branco Weiss Fellowship
- Queens University Belfast
- University of Edinburgh
- Created
-
2017-04-21Created from EPrint's datestamp field
- Updated
-
2021-11-15Created from EPrint's last_modified field