Article révisé par les pairs
Résumé : Ten new companions have emerged from the Keck precision Doppler velocity survey, with minimum (M sin i) masses ranging from 0.8 MJUP to 0.34 M⊙. Five of these are planet candidates with M sin i < 12 MJUP, two are brown dwarf candidates with M sin i ∼ 30 M JUP, and three are low-mass stellar companions. Hipparcos astrometry reveals the orbital inclinations and masses for three of the (more massive) companions, and it provides upper limits to the masses for the rest. A new class of extrasolar planet is emerging, characterized by nearly circular orbits and orbital radii greater than 1 AU. The planet HD 4208b appears to be a member of this new class. The mass distribution of extrasolar planets continues to exhibit a rapid rise from 10 MJUP toward the lowest detectable masses near 1 MSAT.