用于强流直线感应加速器的大面积储备式阴极

Large area dispenser cathode applied to high current linac

介绍一种直径为55mm的锇膜(411M)储备式热阴极,并以此为基础,建立了一套脉冲电压幅度为200kV、脉冲平顶宽度大于等于2μs的长脉冲功率源以及配套的加热系统与高压隔离网络电路。在阴极灯丝工作电流18A,阴极温度1165℃,二极管电压75kV条件下,在该阴极试验平台上获得52A的空间电荷限制流,实验结果与理论计算基本吻合。实验中还发现,阴极的放气源将严重影响阴极发射能力。

The paper introduced a dispenser cathode （411 M） which was 55 mm in diameter. A 200 kV long pulsed power generator with 2 μs flattop based on Marx-PEN and system with heat and voltage insulation were built. A 52 A space charge limited current was gained, when the temperature was 1 165 ℃ and the filament current was 18 A on the cathode and the voltage of the pulse was 75 kV at the cathode test stand. Experimental results show that the current values is consistent with the numerical simulation. The experiment reveals that the deflated gas will influence the cathode emittion ability.