强激光与粒子束, 2014, 26 (11): 115009, 网络出版: 2014-12-08
预充等离子体密度对杆箍缩二极管特性的影响
Effect of plasma density on working characteristics of plasma-filled rod-pinch diode
预充等离子体杆箍缩二极管 等离子体密度 数值模拟 电子沉积密度轴向分布 侧向焦斑 plasma filled rod pinch diode plasma density numerical simulation axial distribution of electron deposition density axial spot
摘要
在杆箍缩二极管工作前预先填充一定密度的等离子体,可以改善二极管特性,从而提高二极管出射X射线的剂量率。建立了预充等离子体的杆箍缩二极管的粒子模拟模型,通过收集轰击到阳极上的电子,诊断其轴向分布,可以给出不同时刻的束流箍缩特性。利用“剑光一号”加速器低阻抗状态(1 MV/9 Ω/40 ns)开展了预充等离子体的杆箍缩二极管实验研究。预充适当密度的等离子体后,二极管阻抗降低到10 Ω,X射线辐射剂量从0.76 mGy提高到3.19 mGy,侧向焦斑从9 mm降到4 mm。模拟结果和实验基本符合。
Abstract
Plasma-filled rod-pinch diode (PFRPD) is a rod-pinch diode (RPD) filled with plasma that injected across the anode-cathode gap using plasma guns prior to the start of diode current. The injected plasma may reduce the impedance of PFRPD and enhance the dose rate of X-rays. A PIC simulating model of PFRPD is established. The beam pinching situation is described by the axial distribution of electron deposition density (ADEDD) on the anode rod. A PFRPD experiment platform is established, where a 1 MV PFRPD is driven by “Jianguang-Ⅰ” accelerator low impedance state(1 MV/9 Ω/40 ns). Experiment results indicate that the diode performs better prefilled with appropriate plasma. The diode impedance is reduced to 10 Ω, X ray radiation dose is increased from 0.76 mGy to 3.19 mGy, axial spot is reduced from 9 mm to 4 mm.
孙剑锋, 孙江, 邱爱慈, 张鹏飞, 杨海亮, 李静雅, 尹佳辉, 胡杨, 金亮. 预充等离子体密度对杆箍缩二极管特性的影响[J]. 强激光与粒子束, 2014, 26(11): 115009. Sun Jianfeng, Sun Jiang, Qiu Aici, Zhang Pengfei, Yang Hailiang, Li Jingya, Yin Jiahui, Hu Yang, Jin Liang. Effect of plasma density on working characteristics of plasma-filled rod-pinch diode[J]. High Power Laser and Particle Beams, 2014, 26(11): 115009.