短脉冲高剂量率γ射线源技术研究

Research on source of high dose rate gamma-ray with short pulse duration

介绍了“强光一号”加速器产生宽度约20ns的高剂量率脉冲γ射线的工作过程;分析了短脉冲γ射线源二极管的管绝缘体和真空磁绝缘传输线的结构与绝缘性能;说明了等离子体断路开关的工作特性;阐述了二极管工作阻抗和阴阳极的设计原则与设计参数。给出了不同短脉冲γ射线源的实验结果,得到了3种辐射参数:脉冲宽度约20ns,辐射面积为2, 30和100cm2 时,相应的辐射剂量率为1011, 0. 7×1011和1010 Gy/s。

One of the important building blocks on Qiangguang-I accelerator is the short-pulse high dose rate gamma-ray source, which is mainly used to generate short pulse intense bremsstrahlung. The process of generating high dose rate gamma-ray with about 20 ns pulse duration on Qiangguang-I accelerator was introduced. The insulating characteristics of insulator and MITL of short-pulse high-impedance intense electron beam diode were analyzed. The characterization of plasma opening switch (POS) was presented. The design approach for diode operating parameters including the diode impedance, cathode and anode was described. The experimental results show that the pulse duration of bremsstrahlung is about 20 ns, and the dose rates at areas of 2, 30 and 100 cm2 are 1011, 0.7 × 1011 and 1010 Gy/s respectively.