BEAM GENERATION, ACCELERATION, AND EXTRACTION ON A STELLATRON ACCELERATOR

The stellatron accelerator of the University of California at Irvine ( UCI) [Phys. Fluids B 2, 3149 (1990)] was modified to accommodate beam extraction. The magnetic field coils were reconstructed to adapt an ex traction port. A fiberglass-graphite-epoxy chamber replaced the glass chamber that cracked frequently during the previous experiment. Improv ement in the magnetic field configuration has significantly reduced th e current loss during acceleration. A 1.1 kA, 12 MeV electron beam was generated by initially forming a 1.2 kA beam with plasma start-up. Th e beam radius was 5-7 mm. Beam extraction was performed with two auxil iary pulsed current coils and up to 15% of the beam was extracted from the chamber. The extraction process was analyzed by computational orb it simulations.