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A Possible Brown Dwarf Companion to the White Dwarf GD1400

J. Farihi·M. Christopher
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Abstract

An unresolved, likely L dwarf companion to the DA white dwarf GD1400 is reported. This would be only the second such system known, discovered 17 years after the prototype L dwarf, GD165B, was determined to be a companion to a white dwarf. Photometric observations and model predicted stellar parameters of the well studied white dwarf primary indicate that GD1400B has $J-K\ga2.0$ and $M_K=12.13$ mag. If correct, this would place GD1400B at spectral type L6, and it would be the lowest luminosity unevolved companion known to a white dwarf, and thus a definite brown dwarf. However, a low resolution Keck NIRSPEC $2.1-2.4μ$m spectrum may not be consistent with known L dwarfs. Uncertainties in classification remain until the binary is resolved or a trigonometric parallax is measured.

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J. Farihi, M. Christopher. 2004-07-01. A Possible Brown Dwarf Companion to the White Dwarf GD1400. https://doi.org/10.1086/423919

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