Empirically establishing relationships between properties of gravitationally collapsing pebble clouds and formed planetesimal systems

During the early stages of the Solar System, nebular gas and sub-mm dust evolved into pebbles, which grew to form planetesimals, which in turn accreted to form proto-planets and eventually the planets that we observe in our current solar system. It’s this process of dust evolving into pebbles that interests us. Because when pebbles reach cm-sizes, growth as a result of pairwise collisions is no longer effective due to growth barriers. On the other hand, growth to planetesimal sizes (1 km - 100 km) can occur via the gravitational collapse of pebble clouds aggregated by interactions between the solid pebbles and the gas disk, as in the streaming instability. To further understand the properties of these collapsing pebble clouds affect the accreted planetesimal systems, we use an use an astrophysical N-body integrator PKDGRAV with its soft-sphere discrete element method In our numerical experiments we are varying the initial random velocities to consider the influence of turbulent mixing in the protoplanetary disk. In all of these scenarios, we are analyzing how these independent variables affect the efficiency of planetesimal accretion, including the final mass of formed planetesimals, the number of accreted planetesimals, the preserved kinetic and potential energy within the system and the multiplicity of planetesimal systems (binary, ternary, etc.). We are interested in the properties of the Kuiper Belt cause we can verify the validity of our simulations, since this subregion has remained untouched since planetesimal formation began in the solar system.