A stream of particles from the β Pictoris disc: A possible ejection mechanism

Recently, a stream for particles originating from the direction of β Pictoris, a young main sequence star surrounded by a dust disc, has been reported (Baggaley 2000). Standard mechanisms of particle ejection from a disc fail to reproduce the properties of this stream. We find that scattering by a giant proto-planet with properties taken from the literature is consistent with the observations. The fact that a straightforward ejection mechanism reproduces the data supports the identification of the particle stream's source with β Pic. Our work also indicates that protoplanetary dust discs form a potentially rich source of large interstellar grains, as widely detected in the Solar System.