Planetesimal Population Synthesis: are Planetesimals formed in Pressure Bumps?

Planetesimals, the smallest building blocks of planets that are gravitationally bound, are believed to be needed in order to form planets. The spacial distribution of these objects that are typically 100 km in diameter is important for the outcome of planet formation. There exist an entire zoo of different disk instabilities that can cause vortices or zonal flow within which pebbles can be trapped and form planetesimals via gravitational instability. We parameterized these traps and implemented a pebble flux-regulated planetesimal formation rate into a dust and gas evolution code. We found that the radial planetesimal distribution spans from the regions of terrestrial planet formation up to the Kuiper belt and is steeper than the initial profile of dust and gas. The latter finding indicates that the feeding zone, i.e. the region from which the material forming planetesimals originates, can be large. The final spacial planetesimal distribution strongly depends on the turbulence strength from which we can conclude that the Solar Nebula was not very turbulent (α<10-2)