Diocotron and Kelvin mode damping from a flux through the critical layer.
Experiments and theory characterize a novel type of spatial Landau damping, caused by a flux of particles through the wave or rotation resonance (critical) layer. Pure electron plasma experiments demonstrate that a steady flux of particles causes algebraic damping of diocotron mode amplitudes for azimuthal modes m = 1 and m = 2, and a simple model of dynamics in the nonlinear cat's eye clarifies the observations. This flux-driven algebraic damping is related to, but distinct from, the exponential decay characteristic of Landau damping. This flux-driven damping applies also to Kelvin waves on 2D vortices, and so may be broadly relevant to plasmas and geophysical flows.
Department of Physics, University of California at San Diego, La Jolla, California 92093, USA.
A A
AA
Kabantsev
Department of Physics, University of California at San Diego, La Jolla, California 92093, USA.
C Y
CY
Chim
Department of Physics, University of California at San Diego, La Jolla, California 92093, USA.
T M
TM
O'Neil
Department of Physics, University of California at San Diego, La Jolla, California 92093, USA.
C F
CF
Driscoll