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The 2MASS Wide-Field T Dwarf Search. V. Discovery of a T Dwarf via Methane Imaging

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 نشر من قبل Simon Ellis
 تاريخ النشر 2005
  مجال البحث فيزياء
والبحث باللغة English
 تأليف S. C. Ellis




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We present the discovery of a T dwarf, 2M2151-4853, via differential imaging through methane filters. The filters are designed to highlight the strong absorption in the H band, due to methane found in the atmospheres of T dwarfs, and provide a very efficient means of searching for them. Subsequent J and H band spectroscopy confirms 2M2151-4853 as a T dwarf of type T4.5. It has an estimated spectrophotometric distance of 18 +/- 3 pc, and an estimated tangential velocity of v=50 +/- 10 km/s.



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