Evolution of the orbit of an asteroid type body within a protoplanetary accretion disc: 3D SPH simulations

Migration of protoplanets within an accretion disc of a forming star seems to be the basic scenario for planetary systems formation. Many details concerning the dragging mechanisms, times and the dominant physical interactions between the protoplanets and the accretion disc are still debated. We report here the results of a study based on 3D Smoothed Particle Hydrodynamic (SPH) simulations, concerning the evolution of the orbital parameters of an asteroid type body embedded in an inviscid accretion disc, with an initially tilted orbit. Both rapid periodic variations of the tilt angle between the fragment angular momentum and the disc mean angular momentum, and a slow monotonic decrease are observed.