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
نویسنده
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 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 is therefore a brown dwarf with mass below 0.065 M ⊙ , and age < ∼ 1.5 Gyr. DBD 1228-1547 can now be the considered prototype for brown dwarfs close to the hydrogen burning limit.
منابع مشابه
ar X iv : a st ro - p h / 05 07 63 5 v 1 2 7 Ju l 2 00 5 MID - INFRARED OBSERVATIONS OF THE WHITE DWARF BROWN DWARF BINARY GD 1400
Fluxes are measured for the DA white dwarf plus brown dwarf pair GD 1400 with the Infrared Array Camera on the Spitzer Space Telescope. GD 1400 displays an infrared excess over the entire 3 − 8µm region consistent with the presence of a mid-to late-type L dwarf companion. A discussion is given regarding current knowledge of this unique system.
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