Transverse two-stream instability of a beam with a Bennett profile

Abstract

A relativistic electron beam magnetically self-focused in a plasma is subject to an electrostatic hose instability. A linear theory of hose growth is formulated, taking into account nonlinear focusing of the beam and collisionless damping due to a plasma gradient. Theory is compared to particle-in-cell simulations of three-dimensional transport of a beam with a Bennett profile, through a broad uniform plasma, as well as a plasma channel matched to the beam.