Effect of nonlinear collective processes on the confinement of a pure-electron plasma

For an electron plasma which is magnetically confined in a cylin- drical field geometry, radial expansion occurs only if the angular momentum of the plasma changes. We discuss nonlinear collective processes by which perturbing, static, asymmetric fields can transfer angular momentum, but not energy, to the plasma and produce radial expansion. For example, the field asymmetry can act as a pump which excites daughter modes via the decay instability. Alternatively, the pump can drive a mode by induced scattering from particles