IBEX - Annular beam propagation experiment

IBEX is a 4-MV, 100-kA, 20-ns cylindrical isolated Blumlein accelerator. In the experiments reported here, the accelerator is fitted with a specially designed foilless diode which is completely immersed in a uniform magnetic field. several diode geometries have been studied as a function of magnetic field strength. The beam propagates a distance of 50 an (∼ 10 cyclotron wavelengths) in vacuum before either striking a beam stop or being extracted through a thin foil. The extracted beam was successfully transported 60 an downstream into a drift pipe filled either with 80 or 640 torr air. The main objectives of this experiment were to establish the proper parameters for the most quiescent 4 MV, 20–40 kA annular beam, and to compare the results with available theory and numerical code simulations.