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A 2MASS L Dwarf Companion to the Nearby K Dwarf GJ 1048

John E. Gizis·J. Davy Kirkpatrick·John C. Wilson
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Abstract

We report the discovery of a probable L1 companion to the nearby K2 dwarf GJ 1048 using the Two Micron All-Sky Survey (2MASS). This source, 2MASSI J0235599-233120 or GJ 1048B, has 2MASS near-infrared colors and absolute magnitudes consistent with an early L dwarf companion with a projected separation of 250 A.U. The L1 spectral type is confirmed by far-red optical and low-resolution IR spectroscopy. We present evidence that GJ 1048 is a young (<~1 Gyr) system, and that GJ 1048B may be a high-mass brown dwarf below the hydrogen-burning limit. Additional studies of the GJ 1048 system will help constrain the characteristics of L dwarfs as a function of age and mass.

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John E. Gizis, J. Davy Kirkpatrick, John C. Wilson. 2000-12-20. A 2MASS L Dwarf Companion to the Nearby K Dwarf GJ 1048. https://doi.org/10.1086/319937

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