Astrometric orbit of a low-mass companion to an ultracool dwarf ?

@article{Sahlmann2013AstrometricOO,
  title={Astrometric orbit of a low-mass companion to an ultracool dwarf ?},
  author={J. Sahlmann and P. Lazorenko and D. S{\'e}gransan and E. Martin and D. Queloz and M. Mayor and S. Udry},
  journal={Astronomy and Astrophysics},
  year={2013},
  volume={556}
}
Little is known about the existence of extrasolar planets around ultracool dwarfs. Furthermore, binary stars with Sun-like primaries and very low-mass binaries composed of ultracool dwarfs show di erences in the distributions of mass ratio and orbital separation that can be indicative of distinct formation mechanisms. Using FORS2/VLT optical imaging for high precision astrometry we are searching for planets and substellar objects around ultracool dwarfs to investigate their multiplicity… Expand

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