Institute of Astronomy

On the Feeding Zone of Planetesimal Formation by Streaming Instability

SpeakerTalk DateTalk Series
Chao-Chin Yang28 July 2014Across HR 2014 Posters


In current theory of planet formation, streaming instability is one of the most promising mechanisms to overcome the meter-barrier in the course of core accretion. Almost all previous studies, however, were focused on a local region of protoplanetary disks with a limited size such that only one radial filamentary concentration of solids was observed. To address this, we conduct the largest-scale simulations of this kind to date, up to 1.6 gas scale heights both horizontally and vertically, with which the vertical stratification of the gas becomes prominent. We demonstrate that large vertical and horizontal extent of the simulation box is indeed required to achieve numerically convergent results. More importantly, we find multiple filamentary concentrations of solids with an average separation of about 0.5 local gas scale heights, which measures the characteristic size of the formation zone of planetesimals by the streaming instability. This result is used to compare with the populations of the asteroid and Kuiper belts in the Solar system.