Near-Infrared Photometry and Spectroscopy of L and T Dwarfs: The Effects of Temperature, Clouds, and Gravity

  title={Near-Infrared Photometry and Spectroscopy of L and T Dwarfs: The Effects of Temperature, Clouds, and Gravity},
  author={Gillian R. Knapp and Sandy K. Leggett and X. L. Fan and Mark. S. Marley and Thomas R. Geballe and David A. Golimowski and Douglas P. Finkbeiner and James E. Gunn and Joseph F. Hennawi and Željko Ivezi{\'c} and Robert H. Lupton and David J. Schlegel and Michael A. Strauss and Zlatan I. Tsvetanov and Kuenley Chiu and Erik Andrew Hoversten and Karl Glazebrook and Wei Zheng and M. Hendrickson and C. C. Williams and Alan K. Uomoto and Frederick John Vrba and Arne Anthon Henden and Christian B. Luginbuhl and Harry H. Guetter and Jeffrey A. Munn and Blaise Canzian and Donald P. Schneider and Jonathan Brinkmann},
  journal={The Astronomical Journal},
  pages={3553 - 3578}
We present new JHK photometry on the MKO-NIR system and JHK spectroscopy for a large sample of L and T dwarfs. Photometry has been obtained for 71 dwarfs, and spectroscopy for 56. The sample comprises newly identified very red objects from the Sloan Digital Sky Survey (SDSS) and known dwarfs from the SDSS and the Two Micron All Sky Survey (2MASS). Spectral classification has been carried out using four previously defined indices from Geballe et al. that measure the strengths of the near… 

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