A Reanalysis of the Fundamental Parameters and Age of TRAPPIST-1

  title={A Reanalysis of the Fundamental Parameters and Age of TRAPPIST-1},
  author={Eileen C. Gonzales and Jacqueline K. Faherty and Jonathan Gagn'e and Johanna K. Teske and Andrew R. McWilliam and Kelle L. Cruz},
  journal={The Astrophysical Journal},
We present the distance-calibrated spectral energy distribution (SED) of TRAPPIST-1 using a new medium resolution (R~6000) near-infrared FIRE spectrum and its Gaia parallax. We report an updated bolometric luminosity (Lbol) of -3.216+/-0.016, along with semi-empirical fundamental parameters: effective temperature Teff=2628+/-42 K, mass=90+/-8 MJup, radius=1.16+/-0.03 RJup, and logg=5.21+/-0.06 dex. It's kinematics point toward an older age while spectral indices indicate youth therefore, we… 
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