大面积均匀电子束产生实验研究

 在电子束泵浦气体激光实验中，大面积均匀电子束是获得高效能激光输出的必要条件。介绍了利用SPG-200脉冲功率源产生大面积均匀电子束的实验。SPG-200是基于SOS的全固态重复频率脉冲功率源，其开路电压大于350 kV。用于产生电子束的真空二极管阴极长294 mm，宽24 mm，两端均为半径为12 mm的半圆，栅网平面为阳极面，两者之间的距离在0~49 mm可调，阴极发射的电子束通过用于隔离激光气室和二极管真空室的压力膜及其支撑栅网引出。分别以石墨和天鹅绒为阴极材料，获得了大面积电子束输出，给出了二极管参数的测量结果，并对电子束发射均匀性进行了诊断。实验结果表明：在阴极材料为石墨、阴阳极间隙为5~9 mm时，二极管电压为240~280 kV，二极管电流为0.7~1.8 kA，输出的电子束很不均匀；在阴极材料为天鹅绒、阴阳极间隙为31~46 mm时，二极管电压为200~250 kV，二极管电流为1.5~1.7 kA，输出的电子束均匀性较好。

Experimental study on generation of large area uniform electron beam

In the experiment of gas laser pumped by electron beam, large area uniform electron beam is important to generate high efficiency laser output. The experimental study on generation of large area uniform electron beam with SPG-200 pulsed power generator is introduced. SPG-200 is an all-solid-state components pulsed power generator based on SOS, and its open voltage is more than 350 kV. The cathode have the area of 24 mm×294 mm, and the anode-cathode(A-C)gap spacing is adjustable from 0 to 49 mm. The electron beam of cathode emission is transported to the laser chamber through the diode pressure foil, which separates the vacuum chamber from the laser chamber. Velvet and graphite cathodes are studied, each generates large area electron beam. The diode parameters are presented, and the unifor