Dwarfs Cooler Than M: The Definition of Spectral Type L Using Discoveries from the 2-Micron All-Sky Survey (2MASS)

  title={Dwarfs Cooler Than M: The Definition of Spectral Type L Using Discoveries from the 2-Micron All-Sky Survey (2MASS)},
  author={J. Davy Kirkpatrick and I. N. Reid and James William Liebert and Roc M. Cutri and Brant O. Nelson and Charles A. Beichman and Conard C. Dahn and David G. Monet and John E. Gizis and Michael F. Skrutskie},
  journal={The Astrophysical Journal},
Before the 2-Micron All-Sky Survey (2MASS) began, only six objects were known with spectral types later than M9.5 V. In the first 371 sq. deg. of actual 2MASS survey data, we have identified another twenty such objects spectroscopically confirmed using the Low Resolution Imaging Spectrograph (LRIS) at the W.M. Keck Observatory. 

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