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Substellar Companions to Main Sequence Stars: No Brown Dwarf Desert at Wide Separations

John E. Gizis·J. Davy Kirkpatrick·Adam Burgasser·I. Neill Reid·David G. Monet·James Liebert·John C. Wilson
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Abstract

We use three field L and T dwarfs which were discovered to be wide companions to known stars by the Two Micron All-Sky Survey (2MASS) to derive a preliminary brown dwarf companion frequency. Observed L and T dwarfs indicate that brown dwarfs are not unusually rare as wide (Delta >1000 A.U.) systems to F-M0 main-sequence stars (M>0.5M_sun, M_V<9.5), even though they are rare at close separation (Delta <3 A.U.), the ``brown dwarf desert.'' Stellar companions in these separation ranges are equally frequent, but brown dwarfs are >~ 10 times as frequent for wide than close separations. A brown dwarf wide-companion frequency as low as the 0.5% seen in the brown dwarf desert is ruled out by currently-available observations.

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John E. Gizis, J. Davy Kirkpatrick, Adam Burgasser, I. Neill Reid, David G. Monet, James Liebert, John C. Wilson. 2001-03-14. Substellar Companions to Main Sequence Stars: No Brown Dwarf Desert at Wide Separations. https://doi.org/10.1086/320017

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