An intense pulsed ion source with a cryogenically refrigerated anode cooled by liquid helium

A new cryogenically refrigerated anode cooled by liquid helium has been constructed. This anode is expected to be capable of a highly repetitive operation, high purity beam generation, and ion species selection. Preliminary experiments were carried out in which our new anode base was cooled to 15 K in a diode chamber by a helium coolant system. Either O2 or N2 gas was su pp1ied th rough an injection nozzle and frozen on the anode base. These materials were adopted as the ion source of a bromine (Br) magnetically insulated diode, for which we renewed our pulse power machine (5-kJ to 500-kV Marx generator and 5-Ω to 70-nsec Blumlein line). This beam generator will be in operation in the near future. In addition, the operating characteristics of the diode and the extracted beams will be clarified.