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.

Radial velocity

Transit photometry

Spectroscopy

Stellar astronomy

Am stars

Brown dwarfs

Stellar rotation

Stellar ages

Author

Jan Subjak

Charles university

Czech Academy of Sciences

Rishikesh Sharma

Yamada Physics Research Laboratory

Theron W. Carmichael

Harvard University

Harvard-Smithsonian Center for Astrophysics

Marshall C. Johnson

Las Cumbres Observ, 6740 Cortona Dr, Suite 102

Erica J. Gonzales

University of California at Santa Cruz

Elisabeth Matthews

Massachusetts Institute of Technology (MIT)

Henri M. J. Boffin

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, Galactic Astrophysics

Leiden University

Tianjun Gan

Tsinghua University

Davide Gandolfi

University of Turin

Rafael A. Garcia

University Paris-Saclay

Paris Diderot University

Eike Guenther

Thüringer Landessternwarte Tautenburg

Artie Hatzes

Thüringer Landessternwarte Tautenburg

David W. Latham

Harvard-Smithsonian Center for Astrophysics

Stephane Mathis

University Paris-Saclay

Paris Diderot University

Savita Mathur

Instituto Astrofisico de Canarias

University of La Laguna

Carina Persson

Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics, Galactic Astrophysics

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

Fisk University

Vanderbilt University

Martin Blazek

Masaryk University

Czech Academy of Sciences

Marek Skarka

Masaryk University

Czech Academy of Sciences

Magdalena Spokova

Masaryk University

Czech Academy of Sciences

Jiri Zak

Masaryk University

Simon Albrecht

Aarhus University

Roi Alonso Sobrino

Instituto Astrofisico de Canarias

University of La Laguna

Paul Beck

University of Graz

Instituto Astrofisico de Canarias

University of La Laguna

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

Massachusetts Institute of Technology (MIT)

Princeton University

Hans J. Deeg

Instituto Astrofisico 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

University of Tokyo

Instituto Astrofisico de Canarias

National Astronomical Observatory of Japan

Iskra Georgieva

Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics, Galactic Astrophysics

Lucia Gonzalez-Cuesta

University of La Laguna

Instituto Astrofisico de Canarias

Sascha Grziwa

University of Cologne

Diego Hidalgo

Instituto Astrofisico 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

Instituto Astrofisico de Canarias

University of La Laguna

Pilar Montanes Rodriguez

University of La Laguna

Instituto Astrofisico de Canarias

Felipe Murgas

University of La Laguna

Instituto Astrofisico de Canarias

Norio Narita

Instituto Astrofisico de Canarias

Astrobiol Ctr

National Astronomical Observatory of Japan

Japan Science and Technology Agency

David Nespral

University of La Laguna

Instituto Astrofisico de Canarias

Prajwal Niraula

Massachusetts Institute of Technology (MIT)

Grzegorz Nowak

Instituto Astrofisico de Canarias

University of La Laguna

Enric Palle

University of La Laguna

Instituto Astrofisico de Canarias

Martin Paetzold

University of Cologne

Jorge Prieto-Arranz

Instituto Astrofisico de Canarias

University of La Laguna

Heike Rauer

German Aerospace Center (DLR)

Freie Universität Berlin

Technische Universität Berlin

Seth Redfield

Wesleyan University

Ignasi Ribas

Institute of Space Studies of Catalonia (IEEC)

Spanish National Research Council (CSIC)

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 4 151

Subject Categories

Astronomy, Astrophysics and Cosmology

Geology

Geosciences, Multidisciplinary

DOI

10.3847/1538-3881/ab7245

More information

Latest update

9/24/2020