Discovery of New Ultracool White Dwarfs in the Sloan Digital Sky Survey

@article{Gates2004DiscoveryON,
  title={Discovery of New Ultracool White Dwarfs in the Sloan Digital Sky Survey},
  author={Evalyn I. Gates and Geza Gyuk and Hugh C. Harris and Mark SubbaRao and Scott Anderson and Scott J. Kleinman and James William Liebert and Howard J. Brewington and Jonathan Brinkmann and Michael Harvanek and Jurek Krzesinski and Donald Q. Lamb and Daniel C. Long and Eric H. Neilsen Jr. and P. R. Newman and Atsuko Nitta and Stephanie A. Snedden},
  journal={The Astrophysical Journal Letters},
  year={2004},
  volume={612},
  pages={L129 - L132}
}
We report the discovery of five new white dwarfs in the Sloan Digital Sky Survey. Four are ultracool, exhibiting strong collision-induced absorption (CIA) from molecular hydrogen and are similar in color to the three previously known coolest white dwarfs, SDSS J1337+00, LHS 3250, and LHS 1402. The fifth star shows milder CIA flux suppression and has a color and spectral shape similar to WD 0346+246. All five new white dwarfs are faint (g > 18.9) and have significant proper motions. One of the… 

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