title: Substrate interactions, effects of symmetry breaking, and convection in a 2D horizontally shaken granular system
abstract: We describe experiments on a horizontally shaken [x = Asin(omegat)] single layer of hard spheres rolling on a nearly horizontal surface. We identify a novel substrate-mediated convective flow which occurs when the system is tilted slightly so that the weak gravitational force, g-->(eff), acting on the particles is not parallel to the driving direction. As the shaking amplitude is increased, the system progresses through four regimes: solid-flat, solid-inclined, convective, and disordered. The control parameter is the driving velocity, Aomega, rather than the usual Aomega(2) of vertically shaken 3D systems. At the onset of convection, the critical velocity is V(c) approximately sqrt[2g(eff)d].
authors.affiliation: Department of Physics and Center for Nonlinear and Complex Systems, Duke University, Durham, North Carolina 27708-0305, USA.
authors.initials: B
authors.lastname: Painter
authors.initials: RP
authors.lastname: Behringer