Planets of β Pictoris revisited

Abstract

Observations have revealed a large variety of structures (global asymmetries, warps, belts, rings) and dynamical phenomena (" fallingevaporating bodies" or FEBs, the "β Pic dust stream") in the disk of βPictoris, most of which may indicate the presence of one or more planets orbiting the star. Because planets of βPic have not been detected by observations yet, we use dynamical simulations to find "numerical evidence" for a planetary system. We show that one planet at 12 AU with a mass of 2 to 5 Mj and an eccentricity ≤0.1 can probably already account for three major features (main warp, two inner belts, FEBs) observed in the β Pic disk. The existence of at least two additional planets at about 25 AU and 45 AU from the star seems likely. We find rather strong upper limits of 0.6 Mj and 0.2 MJ on the masses of those planets. The same planets could, in principle, also account for the outer rings observed at 500-800 AU. © ESO 2007.