New Brown Dwarfs in the Pleiades Cluster

  title={New Brown Dwarfs in the Pleiades Cluster},
  author={Mar{\'i}a Rosa Zapatero Osorio and Rafael Rebolo and E. L. Mart{\'i}n and Gibor Basri and Antonio Magazz{\'u} and Simon T. Hodgkin and Richard F. Jameson and M. R. Cossburn},
  journal={The Astrophysical Journal Letters},
  pages={L81 - L84}
We present intermediate- and low-resolution optical spectroscopy (650-915 nm) of seven faint, very red objects (20>I≥17.8, I-Z≥ 0.5) discovered in a CCD-based IZ survey covering an area of 1 deg2 in the central region of the Pleiades open cluster. The observed spectra show that these objects are very cool dwarfs having spectral types in the range M6-M9. Five out of the seven objects can be considered Pleiades members on the basis of their radial velocities, Hα emissions, and other gravity… 

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