Abstract: A system is disclosed for developing a conditioned electron beam of high quality for an exemplary application to a free-electron source of coherent radiation. The system comprises: a source for producing an electron beam of relatively high energy, a microwave source for generating a microwave field, and a wiggler for generating transverse to the electron beam a periodic magnetic field which cooperates with the microwave field to interact with the electron beam and develop a conditioned electron beam of high quality.

Abstract: A method and apparatus for transporting a positive ion beam to a distant target. An ion channel is created as a path to the target, and the beam injected into the channel at a mildly-relativistic beam velocity. Because the beam is mildly-relativistic, the electric field caused by its positive charge propagates well in advance of the beam, attracting free electrons in the plasma channel and pulling them into the beam along its axis of propagation. The current which is initiated by this precursor electron flow, is sustained during the duration of the beam, and is then a combination of the beam current and additional current carried by the electrons within the channel. As a result, a magnetic flux circulates annularly about the beam of a sufficient magnitude to pinch the beam.