TOI-503: The First Known Brown-dwarf Am-star Binary from the TESS Mission

0534667 - ASÚ 2021 RIV US eng J - Článek v odborném periodiku
Šubjak, Ján - Sharma, R. - Carmichael, T.W. - Johnson, M. C. - Gonzales, E. J. - Matthews, E. - Boffin, H.M.J. - Brahm, R. - Chaturvedi, P. - Chakraborty, A. - Blažek, Martin - Skarka, Marek - Kabáth, Petr - Špoková, Magdaléna … celkem 81 autorů
TOI-503: The First Known Brown-dwarf Am-star Binary from the TESS Mission.
Astronomical Journal. Roč. 159, č. 4 (2020), č. článku 151. ISSN 0004-6256. E-ISSN 1538-3881
Grant CEP: GA ČR(CZ) GC17-01752J
Institucionální podpora: RVO:67985815
Klíčová slova: brown dwarfs * stellar ages * Am stars
Obor OECD: Astronomy (including astrophysics,space science)
Impakt faktor: 6.281, rok: 2020
Způsob publikování: Omezený přístup
https://doi.org/10.3847/1538-3881/ab7245

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).
Trvalý link: http://hdl.handle.net/11104/0312837