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

S. C. Ellis·C. G. Tinney·Adam J. Burgasser·J. Davy Kirkpatrick·Michael W. McElwain
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Abstract

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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S. C. Ellis, C. G. Tinney, Adam J. Burgasser, J. Davy Kirkpatrick, Michael W. McElwain. 2005-08-05. The 2MASS Wide-Field T Dwarf Search. V. Discovery of a T Dwarf via Methane Imaging. https://doi.org/10.1086/491790

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