Orbital Migration and Mass Accretion of Protoplanets in 3D Global Computations with Nested Grids

Gennaro D'Angelo, Wilhelm Kley & Thomas Henning

Astrophysical Journal, 586, 540


We investigate the evolution of protoplanets with different masses embedded in an accretion disk, via global fully three-dimensional hydrodynamical simulations. We consider a range of planetary masses ranging from 3 Earth masses upto one Jupiter mass, and take physically realistic gravitational potentials of the planets into account. To calculate accurately the gravitational torques exerted by disk material and to investigate the accretion process onto the planet, the flow dynamics has to be resolved on large as well as short length scales. We achieve this strict resolution requirement by applying a nested-grid refinement technique which allows to greatly enhance the local resolution.
Our results from alltogether 48 simulations show that for larger planetary masses above approximately 0.1 Jupiter masses the migration rates of the planets are relatively constant and agree well for two- and three-dimensional calculations. Below that mass, we find on average that the smaller the mass of the planets the longer the migration rates. For the mass growth larger differences between two- and three-dimensional calculations are found in particular for planets with smaller masses below about ten earth masses. We derive analytical approximations for the numerically computed migration and mass groth rates.

ApJ-Paper, March 2003 pdf-file (2.1 MB)