RESONANCE TRAPPING IN THE PRIMORDIAL SOLAR NEBULA - THE CASE OF A STOKES DRAG DISSIPATION

We consider the problem of the orbital evolution of solid particles in a gas-rich planetary nebula where one planetary embryo already exists (Weidenschilling and Davis model). The case of a Stokes drag is studied both analytically and numerically. We present the equations of the averaged model for the motion of particles in resonance with the embryo. They allowed us to find stationary solutions (corotations and librations) for a wide range of values of the drag coefficient C, to study the role played by secular resonances, and to discuss the nonexistence of resonance trapping in internal resonances (as previously found by Weidenschilling and Davis) as well as some aspects of the resonance trapping mechanisms. The numerical simulations using the exact equations have shown effective resonance capture in both librations and corotations; in all cases the orbital elements of the evolved (post-trapping) orbits lie in very good agreement with the averaged model predictions. © 1993 by Academic Press, Inc.