DENIS - P J 1228 . 2 - 1547 – A New Benchmark Brown Dwarf
نویسندگان
چکیده
We present optical spectroscopy of three brown dwarf candidates identified in the first 1% of the DENIS sky survey. Low resolution spectra from 6430–9150Å 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±0.05Å equivalent width absorption line of Li I 6708Å, and is therefore a brown dwarf with mass below 0.065 M ⊙ , and age < ∼ 1.5 Gyr. DENIS-P J1228.2-1547 can now be considered a prototype for brown dwarfs closer to the hydrogen burning limit than Gl 229B.
منابع مشابه
ar X iv : a st ro - p h / 97 07 23 9 v 1 2 2 Ju l 1 99 7 A New Benchmark Brown Dwarf
We present optical spectroscopy of three brown dwarf candidates identified in the first 1% of the DENIS sky survey. Low resolution spectra from 6430–9150Å show these objects to have similar spectra to the uncertain brown dwarf candidate GD 165B. High resolution spectroscopy shows that one of the objects – DBD 1228-1547 – has a strong 2.3±0.05Å equivalent width absorption line of Li I 6708Å, and...
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