Experiments in heavy ion fusion beam physics at LBNL, LLNL, and the University of Maryland

A heavy ion fusion driver must be capable of accelerating an intense ion beam to GeV beam energies. The final beam pulse current can be as high as a few kA using beam compression in an induction linac. Combining beamlets at low energy may prove to be economical as long as there is no significant emittance growth. Focusing of the final beam pulse from the reactor chamber wall to the target can be enhanced by using a plasma channel to guide the ion beam. Experiments at LBNL on ion sources, injector, the combiner and plasma channel focusing are discussed. One possible way to reduce the cost of a driver is to use an induction recirculator. Experiments at LLNL are exploring this concept by studying the transport and bending of space-charge-dominated ion beams. At the Univ. of Maryland the behavior of space-charge dominated beams is being simulated with low-energy electrons. They studied emittance growth, halo formation and beam pulse compression.