Richard NELSON : Queen Mary, University of London
The role of migration in the formation of planets
I will begin by reviewing the observational evidence for disc-induced orbital migration of planets, and then describe the basic theory of disc-planet interactions: type I migration of low mass planets; type II migration of high mass gap-forming planets. Unattenuated type I migration remains a problem for forming gas giant planets through the core instability model, and I will review the successes and failures of different ideas for preventing and/or slowing migration of low mass planets (turbulence, planet-planet scattering, strong magnetic fields, corotation torques, ...). The latter part of my talk will focus on the role of MHD turbulence in protoplanetary discs. I will discuss the results of simulations of planetesimals and planets (high and low mass) interacting with "cylindrical" turbulent discs, and their consequences for planet formation. I will finish by presenting prelimary results for low mass planets embedded in recently computed vertically stratified disc models.Last modified: Sun Jul 9 18:08:02 2006