A Method for Determining the Physical Properties of the Coldest Known Brown Dwarfs

@article{Burgasser2005AMF,
  title={A Method for Determining the Physical Properties of the Coldest Known Brown Dwarfs},
  author={Adam J. Burgasser and Adam Burrows and J. Davy Kirkpatrick},
  journal={The Astrophysical Journal},
  year={2005},
  volume={639},
  pages={1095-1113}
}
We present a method for measuring the physical parameters of the coldest T-type brown dwarfs using lowresolution near-infrared spectra. By comparing H_(2)O and H_2-sensitive spectral ratios between empirical data and theoretical atmosphere models, and calibrating these ratios to measurements for the well-characterized 2–5 Gyr companion brown dwarf Gliese 570D, we derive estimates of the effective temperatures and surface gravities for 13 mid- and late-type field T dwarfs. We also deduce the… 
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