Substellar Companions to Main Sequence Stars: No Brown Dwarf Desert at Wide Separations
Astrophysics
2009-11-06 v1
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.
Cite
@article{arxiv.astro-ph/0103219,
title = {Substellar Companions to Main Sequence Stars: No Brown Dwarf Desert at Wide Separations},
author = {John E. Gizis and J. Davy Kirkpatrick and Adam Burgasser and I. Neill Reid and David G. Monet and James Liebert and John C. Wilson},
journal= {arXiv preprint arXiv:astro-ph/0103219},
year = {2009}
}
Comments
ApJL, in press