TOI-503: The First Known Brown-dwarf Am-star Binary from the TESS Mission
Journal article, 2020
We report the discovery of an intermediate-mass transiting brown dwarf (BD), TOI-503b, from the TESS mission. TOI-503b is the first BD discovered by TESS, and it has circular orbit around a metallic-line A-type star with a period of P.=.3.6772.+/-.0.0001 days. The light curve from TESS indicates that TOI-503b transits its host star in a grazing manner, which limits the precision with which we measure the BD's radius ( = R 1.34+ R b 0.150.26 J). We obtained highresolution spectroscopic observations with the FIES, Ondr.ejov, PARAS, Tautenburg, and TRES spectrographs, and measured the mass of TOI-503b to be Mb.=.53.7.+/-.1.2 MJ. The host star has a mass of Ma.=.1.80.+/-.0.06Me, a radius of Ra.=.1.70.+/-.0.05Re, an effective temperature of Teff.=.7650.+/-.160 K, and a relatively high metallicity of 0.61.+/-.0.07 dex. We used stellar isochrones to derive the age of the system to be 180 Myr, which places its age between that of RIK 72b (a 10 Myr old BD in the Upper Scorpius stellar association) and AD 3116b (a 600 Myr old BD in the Praesepe cluster). Given the difficulty in measuring the tidal interactions between BDs and their host stars, we cannot precisely say whether this BD formed in situ or has had its orbit circularized by its host star over the relatively short age of the system. Instead, we offer an examination of plausible values for the tidal quality factor for the star and BD. TOI-503b joins a growing number of known short-period, intermediate-mass BDs orbiting mainsequence stars, and is the second such BD known to transit an A star, after HATS-70b. With the growth in the population in this regime, the driest region in the BD desert (35-55MJ sin i) is reforesting.
Am stars
Brown dwarfs
Stellar rotation
Stellar ages
Spectroscopy
Transit photometry
Radial velocity
Stellar astronomy
Author
Jan Subjak
Czech Academy of Sciences
Charles University
Rishikesh Sharma
Yamada Physics Research Laboratory
Theron W. Carmichael
Harvard-Smithsonian Center for Astrophysics
Harvard University
Marshall C. Johnson
Las Cumbres Observatory Global Telescope Network
Erica J. Gonzales
University of California at Santa Cruz
Elisabeth Matthews
Massachusetts Institute of Technology (MIT)
Henri M. J. Boffin
European Southern Observatory (ESO)
Rafael Brahm
Pontificia Universidad Catolica de Chile
Millennium Institute of Astrophysics
Priyanka Chaturvedi
Thüringer Landessternwarte Tautenburg
Abhijit Chakraborty
Yamada Physics Research Laboratory
David R. Ciardi
California Institute of Technology (Caltech)
Karen A. Collins
Harvard-Smithsonian Center for Astrophysics
Massimiliano Esposito
Thüringer Landessternwarte Tautenburg
Malcolm Fridlund
Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics
Leiden University
Tianjun Gan
Tsinghua University
Davide Gandolfi
University of Turin
Rafael A. Garcia
Paris Diderot University
University Paris-Saclay
Eike Guenther
Thüringer Landessternwarte Tautenburg
Artie Hatzes
Thüringer Landessternwarte Tautenburg
David W. Latham
Harvard-Smithsonian Center for Astrophysics
Stephane Mathis
Paris Diderot University
University Paris-Saclay
Savita Mathur
Instituto de Astrofísica de Canarias
University of La Laguna
Carina Persson
Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics
Howard M. Relles
Harvard-Smithsonian Center for Astrophysics
Joshua E. Schlieder
NASA Goddard Space Flight Center
Thomas Barclay
NASA Goddard Space Flight Center
Courtney D. Dressing
University of California
Ian Crossfield
Massachusetts Institute of Technology (MIT)
Andrew W. Howard
California Institute of Technology (Caltech)
Florian Rodler
European Southern Observatory Santiago
George Zhou
Harvard-Smithsonian Center for Astrophysics
Samuel N. Quinn
Harvard-Smithsonian Center for Astrophysics
Gilbert A. Esquerdo
Harvard-Smithsonian Center for Astrophysics
Michael L. Calkins
Harvard-Smithsonian Center for Astrophysics
Perry Berlind
Harvard-Smithsonian Center for Astrophysics
Keivan G. Stassun
Vanderbilt University
Fisk University
Martin Blazek
Masaryk University
Czech Academy of Sciences
Marek Skarka
Czech Academy of Sciences
Masaryk University
Magdalena Spokova
Czech Academy of Sciences
Masaryk University
Jiri Zak
Masaryk University
Simon Albrecht
Aarhus University
Roi Alonso Sobrino
Instituto de Astrofísica de Canarias
University of La Laguna
Paul Beck
University of La Laguna
Instituto de Astrofísica de Canarias
University of Graz
Juan Cabrera
German Aerospace Center (DLR)
Ilaria Carleo
Wesleyan University
William D. Cochran
The University of Texas at Austin
Szilard Csizmadia
German Aerospace Center (DLR)
Fei Dai
Princeton University
Massachusetts Institute of Technology (MIT)
Hans J. Deeg
Instituto de Astrofísica de Canarias
University of La Laguna
Jerome P. de Leon
University of Tokyo
Philipp Eigmueller
German Aerospace Center (DLR)
Michael Endl
The University of Texas at Austin
Anders Erikson
German Aerospace Center (DLR)
Akihiko Fukui
Instituto de Astrofísica de Canarias
University of Tokyo
National Astronomical Observatory of Japan
Iskra Georgieva
Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics
Lucia Gonzalez-Cuesta
Instituto de Astrofísica de Canarias
University of La Laguna
Sascha Grziwa
University of Cologne
Diego Hidalgo
Instituto de Astrofísica de Canarias
University of La Laguna
Teruyuki Hirano
Tokyo Institute of Technology
Maria Hjorth
University of Graz
Emil Knudstrup
University of Graz
Judith Korth
University of Cologne
Kristine W. F. Lam
Technische Universität Berlin
John H. Livingston
University of Tokyo
Mikkel N. Lund
Aarhus University
Rafael Luque
University of La Laguna
Instituto de Astrofísica de Canarias
Pilar Montanes Rodriguez
University of La Laguna
Instituto de Astrofísica de Canarias
Felipe Murgas
University of La Laguna
Instituto de Astrofísica de Canarias
Norio Narita
Instituto de Astrofísica de Canarias
National Astronomical Observatory of Japan
Astrobiology Center, Japan
Japan Science and Technology Agency
David Nespral
University of La Laguna
Instituto de Astrofísica de Canarias
Prajwal Niraula
Massachusetts Institute of Technology (MIT)
Grzegorz Nowak
University of La Laguna
Instituto de Astrofísica de Canarias
Enric Palle
Instituto de Astrofísica de Canarias
University of La Laguna
Martin Paetzold
University of Cologne
Jorge Prieto-Arranz
University of La Laguna
Instituto de Astrofísica de Canarias
Heike Rauer
Freie Universität Berlin
Technische Universität Berlin
German Aerospace Center (DLR)
Seth Redfield
Wesleyan University
Ignasi Ribas
Spanish National Research Council (CSIC)
Institute of Space Studies of Catalonia (IEEC)
Alexis M. S. Smith
German Aerospace Center (DLR)
Vincent Van Eylen
Princeton University
Petr Kabath
Czech Academy of Sciences
Astronomical Journal
0004-6256 (ISSN) 1538-3881 (eISSN)
Vol. 159 4 151Subject Categories
Astronomy, Astrophysics and Cosmology
Geology
Geosciences, Multidisciplinary
DOI
10.3847/1538-3881/ab7245