Title: Numerical Simulations of Saturn's B Ring: Granular Friction as a Mediator between Self-Gravity and Viscous Overstability,
Abstract: We study the B ring's complex optical depth structure. The source of this
structure may be the complex dynamics of the Keplerian shear and the
self-gravity of the ring particles. The outcome of these dynamic effects
depends sensitively on the collisional and physical properties of the
particles. Two mechanisms can emerge that dominate the macroscopic physical
structure of the ring: self-gravity wakes and viscous overstability. Here we
study the interplay between these two mechanisms by using our recently
developed particle collision method that allows us to better model the
inter-particle contact physics. We find that for a constant ring surface
density and particle internal density, particles with rough surfaces tend to
produce axisymmetric ring features associated with the viscous overstability,
while particles with smoother surfaces produce self-gravity wakes.