The Missing Link: Early Methane ("T") Dwarfs in the Sloan Digital Sky Survey.

  title={The Missing Link: Early Methane ("T") Dwarfs in the Sloan Digital Sky Survey.},
  author={Leggett and Geballe and Fan and Schneider and Gunn and Lupton and Knapp and Strauss and McDaniel and Golimowski and Henry and Peng and Tsvetanov and Uomoto and Zheng and Hill and Ramsey and Anderson and Annis and Bahcall and Brinkmann and Chen and Csabai and Fukugita and Hennessy and Hindsley and Ivezi{\'c} and Lamb and Munn and Pier and Schlegel and Smith and Stoughton and Thakar and York},
  journal={The Astrophysical journal},
  volume={536 1},
We report the discovery of three cool brown dwarfs that fall in the effective temperature gap between the latest L dwarfs currently known, with no methane absorption bands in the 1-2.5 µm range, and the previously known methane (T) dwarfs, whose spectra are dominated by methane and water. The newly discovered objects were detected as very red objects in the Sloan Digital Sky Survey imaging data and have JHK colors between the red L dwarfs and the blue Gl 229B-like T dwarfs. They show both CO… 
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