UC Irvine

Relativistic electron beams propagating in long plasma columns must be well focused to cause efficient plasma heating. Expansion of the beam area due to scattering lowers efficiency. We calculate the beam spreading expected from errors in the ambient magnetic field. We then include scattering from both electrostatic and magnetic waves generated by the beam itself. All these effects can be important in contemplated experimental regimes. However, it may prove possible to ’’tune’’ beam-plasma heating processes to avoid significant beam spreading.