Description
The discovery of 9 new brown-dwarf candidates is reported. New CORALIE radial velocities of 6 previously-known hosts of potential brown-dwarf companions are presented. We use Hipparcos data to fully characterise the astrometric orbits of 6 objects, revealing M-dwarf companions with masses between 90M_Jup_ and 0.52M_{sun}_. We obtain an upper limit of 0.6% for the frequency of brown-dwarf companions around Sun-like stars. We find that the companion-mass distribution function is rising at the lower end of the brown-dwarf mass range, suggesting that in fact we detect the high-mass tail of the planetary distribution.
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