First determination of the dynamical mass of a binary L dwarf

  title={First determination of the dynamical mass of a binary L dwarf},
  author={Herv{\'e} Bouy and Gaspard Duch{\^e}ne and Rainer Koehler and Wolfgang Brandner and J{\'e}r{\^o}me Bouvier and E. L. Mart{\'i}n and Andrea M. Ghez and Xavier Delfosse and Thierry Forveille and France Allard and Isabelle Baraffe and Gibor Basri and Laird M. Close and Caer-Eve McCabe},
  journal={Astronomy and Astrophysics},
We present here the results of astrometric, photometric and spectroscopic observations leading to the determination of the orbit and dynamical masses of the binary L dwarf 2MASSW J0746425+2000321. High angular resolution observations spread over almost 4 years and obtained with the Hubble Space Telescope (HST), the ESO Very Large Telescope (VLT), and at heW. M. Keck Observatory (Keck) allow us to cover ∼36% of the period, corresponding to 60% of the orbit, and, for the first time, to derive a… 

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