5MV proton beam generation, focusing and target irradiation

A high voltage ion diode experiments and its focusing onto targets were performed on Reiden-IV-H accelerator combined with an inductive storage pulse compression system. In plane anode experiments, a voltage scaling of a diode brightness were obtained in applied magnetic field diode and the brightness of larger than 100 TW/cm2rad2 were obtained at 5 MeV operation. The diode brightness increased proportionally to the square of the voltage. The proton beam divergence was inversely proportional to an anode-cathode gap. An anode ion image taken by a high resolution (ΔR approx. = 25μm) ion pinhole camera showed a localized ion emission at the edges of grooves of the anode ion source. These data implies that the ion current density, and therefore the strength of voltage dependence of the diode brightness was not a space charge limited value but was limited by the ion source. To avoid this limitation and make fast the anode turn on time, an active anode ion source experiments are pursuing