Sculpting Planetary Systems via Dynamical Processes

Dynamical processes can sculpt the orbital and structural properties of planets in multiplanet systems. For example, planet-planetesimal interactions can naturally explain the strange asymmetric distribution of period ratios of adjacent planet pairs across the 3:2 and 2:1 mean motion resonances. On the other hand, the observed distribution of Hill separations between planet pairs may be a direct consequence of planet-planet scattering. Planet-planet scattering between the typical short-period and puffy exoplanets often leads to planet-planet collisions. The unique structures of these planets indicate that such collisions often may not lead to merger of these planets. Using various numerical techniques including direct N-body simulations, one-dimensional hydrostatic models, and detailed smooth-particle hydrodynamics models we have studied all of the above dynamical processes. I will present the highlights of our research efforts.