Kepler-503b: An Object at the Hydrogen Burning Mass Limit Orbiting a Subgiant Star
AuthorCañas, Caleb I.
Fleming, Scott W.
Beatty, Thomas G.
Covey, Kevin R.
Lee, Nathan De
Hearty, Fred R.
García-Hernández, D. A.
Majewski, Steven R.
Schneider, Donald P.
Stassun, Keivan G.
Wilson, Robert F.
AffiliationUniv Arizona, Dept Astron
MetadataShow full item record
PublisherIOP PUBLISHING LTD
CitationCaleb I. Cañas et al 2018 ApJL 861 L4
JournalASTROPHYSICAL JOURNAL LETTERS
Rights© 2018. The American Astronomical Society. All rights reserved.
Collection InformationThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at email@example.com.
AbstractUsing spectroscopic radial velocities with the Apache Point Observatory Galaxy Evolution Experiment (APOGEE) instrument and Gaia distance estimates, we demonstrate that Kepler-503b, currently considered a validated Kepler planet, is in fact a brown-dwarf/low-mass star in a nearly circular 7.2-day orbit around a subgiant star. Using a mass estimate for the primary star derived from stellar models, we derive a companion mass and radius of 0.075 +/- 0.003 M-circle dot (78.6 +/- 3.1 M-Jup) and 0.099(-0.004)(+0.006) R-circle dot(0.966(-0.04)(+0.06) R-Jup), respectively. Assuming that the system is coeval, the evolutionary state of the primary indicates the age is similar to 6.7 Gyr. Kepler-503b sits right at the hydrogenburning mass limit, straddling the boundary between brown dwarfs and very low-mass stars. More precise radial velocities and secondary eclipse spectroscopy with the James Webb Space Telescope (JWST) will provide improved measurements of the physical parameters and age of this important system to better constrain and understand the physics of these objects and their spectra. This system emphasizes the value of radial velocity observations to distinguish a genuine planet from astrophysical false positives, and is the first result from the Sloan Digital Sky Survey (SDSS)-IV monitoring of Kepler planet candidates with the multi-object APOGEE instrument.
VersionFinal published version
SponsorsNSF [AST 1517592, 1616684, 1616636]; Spanish Ministry of Economy and Competitiveness (MINECO) [AYA-2017-88254-P]; NASA [NAS5-26555]; NASA Office of Space Science [NNX09AF08G]; NASA; NSF; NASA Science Mission directorate; Alfred P. Sloan Foundation; U.S. Department of Energy Office of Science; University of Utah; Brazilian Participation Group; Carnegie Institution for Science; Carnegie Mellon University; Chilean Participation Group; French Participation Group; Harvard-Smithsonian Center for Astrophysics; Instituto de Astroffsica de Canarias; Johns Hopkins University; Kavli Institute for the Physics and Mathematics of the Universe (IPMU)/University of Tokyo; Lawrence Berkeley National Laboratory; Leibniz Institut fur Astrophysik Potsdam (AIP); Max-Planck-Institut fur Astronomic (MPIA Heidelberg); Max-Planck-Institut fur Astrophysik (MPA Garching); Max-Planck-Institut fur Extraterrestrische Physik (MPE); National Astronomical Observatories of China; New Mexico State University; New York University; University of Notre Dame; Observatario Nacional/MCTI; Ohio State University; Pennsylvania State University; Shanghai Astronomical Observatory; United Kingdom Participation Group; Universidad Nacional Autonoma de Mexico; University of Arizona; University of Colorado Boulder; University of Oxford; University of Portsmouth; University of Virginia; University of Washington; University of Wisconsin; Vanderbilt University; Yale University