The Substellar Population of the Young Cluster λ Orionis

  title={The Substellar Population of the Young Cluster $\lambda$ Orionis},
  author={David Barrado y Navascu{\'e}s and John R. Stauffer and J{\'e}r{\^o}me Bouvier and Ray Jayawardhana and Jean-Charles Cuillandre},
  journal={The Astrophysical Journal},
  pages={1064 - 1078}
By collecting optical and infrared photometry and low-resolution spectroscopy, we have identified a large number of low-mass stars and brown dwarf candidates belonging to the young cluster (∼5 Myr) associated with the binary star λ Orionis. The lowest mass object found is an M8.5 with an estimated mass of 0.02 M⊙ (∼0.01 M⊙ for objects without spectroscopic confirmation). For those objects with spectroscopy, the measured strength of the Hα emission line follows a distribution similar to other… 

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