2001ApJ...551L.163G

We use three field L and T dwarfs that were discovered to be wide companions to known stars by the Two Micron All-Sky Survey to derive a preliminary brown dwarf companion frequency. Observed L and T dwarfs indicate that brown dwarfs are not unusually rare as wide (Δ>1000 AU) systems to F-M0 main-sequence stars (M>0.5 M_☉, M_V<9.5), even though they are rare at close separation (Δ<3 AU; 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.