Two Intermediate-mass Transiting Brown Dwarfs from the TESS Mission

摘要: We report the discovery of two intermediate-mass transiting brown dwarfs (BDs), TOI-569b and TOI-1406b, from NASA's Transiting Exoplanet Survey Satellite mission. has an orbital period P=.55604±0.00016 days, a mass Mb = 64.1±1.9 MJ, radius Rb 0.75±0.02 RJ. Its host star, TOI-569, Ma 1.21±0.05 M, Ra 1.47±0.03 R, [Fe H 0.29 0.09] + dex, effective temperature Teff 5768±10K. TOI-1406b P=10.57415±0.00063 46.0± 2.7 0.86±0.03 The star for this BD 1.18±0.09 1.35±0.03 [Fe/H] =-0.08± 0.09 6290±100 K. Both BDs are in circular orbits around their stars older than 3 Gyr based on stellar isochrone models stars. TOI-569 is one slightly evolved known to (the other being KOI-415). three occupy range 40-50 MJ have orbit at near 10 days (with first KOI-205b). reliable ages isochrones, addition well-constrained masses radii, making them particularly valuable as tests substellar isochrones mass-radius diagram.