Takahashi Y, Miyamoto N, Kasuya T, Wada M
Graduate School of Engineering, Doshisha University, Kyoto 610-0321, Japan.
Rev Sci Instrum. 2012 Feb;83(2):02B910. doi: 10.1063/1.3672470.
A tungsten filament cathode has been operated with an ac heating current to excite a plasma in a linear magnetic field. Both the discharge current and the ion saturation current in plasma near the extraction hole of the ion source exhibited fluctuations. The discharge current fluctuated with the amplitude less than 2% of the average, and the frequency two times the frequency of the heating current. Fluctuation amplitude of the ion saturation current was about 10% of the average, while the frequency was the same as that of the heating current. The ac operation has prolonged the lifetime of a hot filament cathode by about 50%.
钨丝阴极已通过交流加热电流运行，以在线性磁场中激发等离子体。离子源引出孔附近等离子体中的放电电流和离子饱和电流均呈现出波动。放电电流的波动幅度小于平均值的2%，频率为加热电流频率的两倍。离子饱和电流的波动幅度约为平均值的10%，而频率与加热电流相同。交流运行使热丝阴极的寿命延长了约50%。
