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Title: TOI-1994b: A Low-mass Eccentric Brown Dwarf Transiting A Subgiant Star

We present the discovery of TOI-1994b, a low-mass brown dwarf transiting a hot subgiant star on a moderately eccentric orbit. TOI-1994 has an effective temperature of7700410+720K, Vmagnitude of 10.51 mag and log(g) of3.9820.065+0.067. The brown dwarf has a mass of22.12.5+2.6MJ, a period of 4.034 days, an eccentricity of0.3410.059+0.054, and a radius of1.2200.071+0.082RJ. TOI-1994b is more eccentric than other transiting brown dwarfs with similar masses and periods. The population of low-mass brown dwarfs may have properties similar to planetary systems if they were formed in the same way, but the short orbital period and high eccentricity of TOI-1994b may contrast this theory. An evolved host provides a valuable opportunity to understand the influence stellar evolution has on the substellar companion’s fundamental properties. With precise age, mass, and radius, the global analysis and characterization of TOI-1994b augments the small number of transiting brown dwarfs and allows the testing of substellar evolution models.

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Author(s) / Creator(s):
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DOI PREFIX: 10.3847
Date Published:
Journal Name:
The Astronomical Journal
Medium: X Size: Article No. 109
["Article No. 109"]
Sponsoring Org:
National Science Foundation
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