Development of Multi-purpose Repetitive Pulsed Ion Beam Driver with Cryodenic Anode

我们试图研制一种新型多用途脉冲离子束驱动器，它以高纯材料覆盖的低温阳极作为离子源，具有产生各种脉冲离子束的高性能，脉冲持续时间短，纯度高，可重复生产。研制了一台重复频率为0.2Hz的脉冲功率机，采用低温阳极磁绝缘二极管，实现了高纯脉冲离子束的连续重复运转，并成功地在20 K的阳极上制冰，引出了高纯氮离子束。建造和运营。实验结果表明：1.研制了一套液氦冷却的低温阳极系统，在单次工作条件下，系统性能达到500 KV-100 KA-50 ns;在重复工作条件下，系统性能达到300 KV-60 KA-50 ns。并成功地从5K.3的氢冰中产生了高纯质子束流。我们还研制了一套封闭循环的气体氦循环阳极冷却系统，该系统采用逆斯特林循环在此基础上，利用制冷机和鼓风机，获得了20 K-15 W的阳极连续冷却能力，从氮冰中引出了高纯氮束流。4.成功地产生了0.2Hz的重复性束流，5.从H_2O或D_2O中提取出H ^+或D^+离子束，具有良好的重复性。最大束流功率约为2GW，观察到离子流与二极管电压、阳极源材料和温度的关系。6.介绍了改进或新发展的束流测量技术，这使得我们能够定量地测量束纯度并评估温度对阳极等离子体形成过程的影响。

We tried to develop a new trpe of multi-purpose pulsed ion beam driver which had a cryofenic anode covered with a high purity material as the ion source and which had high performances to produce various kinds of pulsed ion beams with a short time duration,high purity and repetitive production capability. A pulsed power machine with 0.2Hz repetition frequency was constructed,and magnetically insulated diodes with cryogenic anodes were operated to expetitive pulsed ion beams with high purity.As the main result,we succeeded to make ices on the anodes of 20K and to extract high purity nitrogen beams under semicontinuous repetitive operations.The contents of our research results are summarized as follows.1.A new pulsed power machine was designed,constructed and operated. The system performance of the machine were assured tobe 500KV-100KA-50ns under the single shot operation and 300KV-60KA-50ns under the repetitive operation.2.We developed a cryogenic anode system with liquid helium cooling,and succeeded to produce high purity proton beams from hydrogen ices of 5K.3.We also developed a closed cycle gas helium circulating anode cooling system with a inverse Stirling cycle refrigerator and a gas blower, with which we obtained a continuous cooling capacity of 20K-15W on the anode.High purity nitrogen beams were extracted from nitrogen ices.4.Repetitive beam productions of 0.2Hz were successful,which contributed to asses our future cryogenic diodes in plan.5.H^+ or D^+ beam was extracted with a good reproducibility from H_2O or D_2O ise under liquid nitrogen cooling.The maximum beam power was about 2GW,and the ion currents were observed as the functions of the diode voltage,the anode source materials and the temperature.6.Revised or newly developed beam measuring techniques were introduced, which enabled us to measure the beam purity quantitatively and to evaluate the temperature effects on the anode plasma formation processes.