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DENIS-P J1228.2-1547 -- A New Benchmark Brown Dwarf

C. G. Tinney·X. Delfosse·T. Forveille
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Abstract

We present optical spectroscopy of three brown dwarf candidates identified in the first 1% of the DENIS sky survey. Low resolution spectra from 6430 - 9150A show these objects to have similar spectra to the brown dwarf candidate GD 165B. High resolution spectroscopy shows that one of the objects -- DENIS-P J1228.2-1547 -- has a strong 2.3+-0.05A equivalent width absorption line of Li I 6708A, and is therefore a brown dwarf with mass below 0.065Msol, and age < 1.5 Gyr. DENIS-P J1228.2-1547 can now be considered a proto-type for brown dwarfs closer to the hydrogen burning limit than Gl 229B.

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C. G. Tinney, X. Delfosse, T. Forveille. 1997-09-22. DENIS-P J1228.2-1547 -- A New Benchmark Brown Dwarf. https://doi.org/10.1086/311011

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