Collisional Dynamics of Perturbed Planetary Rings. I.
Local simulations of the outer edge of the Encke gap are presented that use particles of approximately the proper size and optical depth but ignore self-gravity. These simulations clearly show the formation and damping of wakes caused by the moonlet Pan. In this paper we focus primarily on shear reversal and the values of the pressure tensor in this system. We observe angular momentum luminosity reversal in the simulations, lending support to the prediction that this process could be responsible for the sharp edges seen at the Encke gap. We also find evidence for vertical splashing of particles out of the ring plane at the wake peaks. This vertical splashing violates assumptions made in many analytic treatments of this region but does not appear to invalidate the main conclusions drawn from those models. In addition, we find that the maximum amplitude of the wakes is limited by localized displacements of the particles' semimajor axes near the wake peaks.
Document Object Identifier (DOI)
American Astronomical Society
Lewis, M. C., & Stewart, G. R. (2000). Collisional dynamics of perturbed planetary rings. I. Astronomical Journal, 120(6), 3295-3310. doi:10.1086/316853