TOI-503: The First Known Brown-dwarf Am-star Binary from the TESS Mission
Artikel i vetenskaplig tidskrift, 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}_{b}={1.34}_{-0.15}^{+0.26}{R}_{{\rm{J}}} ). We obtained high-resolution spectroscopic observations with the FIES, Ondřejov, PARAS, Tautenburg, and TRES spectrographs, and measured the mass of TOI-503b to be Mb = 53.7 ± 1.2 ${M}_{{\rm{J}}} . The host star has a mass of M⋆ = 1.80 ± 0.06 M☉, a radius of R⋆ = 1.70 ± 0.05R☉, 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 main-sequence 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\mbox{--}55{M}_{{\rm{J}}}\sin i ) is reforesting.

Spectroscopy

Transit photometry

Brown dwarfs

Stellar rotation

Stellar astronomy

Am stars

Stellar ages

Radial velocity

Författare

J. Subjak

R Sharma

Th. W. Carmichael

M. C. Johnson

Erica J. Gonzales

Elisabeth Matthews

Henri M. J. Boffin

Rafael Brahm

Priyanka Chaturvedi

Abhijit Chakraborty

David R. Ciardi

Karen A. Collins

Massimiliano Esposito

Malcolm Fridlund

Chalmers, Rymd-, geo- och miljövetenskap, Astronomi och plasmafysik, Galaktisk astrofysik

Tianjun Gan

Davide Gandolfi

Rafael A. Garcia

Eike Guenther

Artie Hatzes

David W. Latham

Stephane Mathis

Savita Mathur

Carina Persson

Chalmers, Rymd-, geo- och miljövetenskap, Astronomi och plasmafysik, Galaktisk astrofysik

Howard M. Relles

Joshua E. Schlieder

Thomas Barclay

Courtney D. Dressing

Ian Crossfield

A. W. Howard

Florian Rodler

George Zhou

Samuel N. Quinn

Gilbert A. Esquerdo

Michael L. Calkins

Perry Berlind

Keivan G. Stassun

Martin Blazek

Marek Skarka

Magdalena Spokova

Jiri Zak

Simon Albrecht

Roi Alonso Sobrino

Paul Beck

Juan Cabrera

Ilaria Carleo

W. D. Cochran

Szilard Csizmadia

Fei Dai

Hans Deeg

Jerome de Leon

Philipp Eigmueller

Michael Endl

Anders Erikson

Akihiko Fukui

Iskra Georgieva

Chalmers, Rymd-, geo- och miljövetenskap, Astronomi och plasmafysik, Galaktisk astrofysik

Lucia Gonzalez-Cuesta

Sascha Grziwa

Diego Hidalgo

Teruyuki Hirano

Maria Hjorth

Emil Knudstrup

Judith Korth

Kristine W. F. Lam

John H. Livingston

Mikkel N. Lund

Rafael Luque

Pilar Montanes Rodriguez

Felipe Murgas

Norio Narita

David Nespral

Prajwal Niraula

Grzegorz Nowak

Enric Palle

Martin Pätzold

Jorge Prieto-Arranz

Heike Rauer

Seth Redfield

Ignasi Ribas

Alexis M.S. Smith

Vincent Van Eylen

Petr Kabath

Astronomical Journal

0004-6256 (ISSN) 1538-3881 (eISSN)

Vol. 159 151-

Exoplaneter från rymden - CHEOPS och PLATO

Rymdstyrelsen, 2017-01-01 -- 2022-12-31.

Ämneskategorier

Astronomi, astrofysik och kosmologi

Fundament

Grundläggande vetenskaper

DOI

10.3847/1538-3881/ab7245

Mer information

Skapat

2020-05-07