本项目对应“电磁能装备材料极端条件等价试验与测量技术”研究方向的“发射体形貌连续观测技术”。杆箍缩二极管（RPD）是目前普遍采用的脉冲硬X射线源，但存在阻抗高、功率密度低等问题，且无法实现分幅照相。为此本项目提出利用金属丝电爆炸等离子体断路开关（POS）降低RPD阻抗并配合快直线变压器驱动源（FLTD）调控电子束箍缩动力学行为的新思路，首先基于现有4级FLTD装置，研究POS开断产生高压快脉冲形成高亮度近球形脉冲点源的物理过程并实现单幅照相时间分辨<1μs、空间分辨<0.1mm；在此基础上探索通过调控FLTD触发时序产生百ns-百μs级延时可调脉冲串以驱动POS多次通断，进而实现单发放电、多脉冲辐射的可行性；同时结合激光探针精密诊断及磁流体与粒子模拟，研究多脉冲驱动下低阻抗RPD电子束与等离子体动力学行为，阐明其辐射特性及调控机理。研究可为发射体形貌连续高分辨率观测装置的研制提供重要支撑。

The project corresponds to the topic “continuous projectile morphology diagnostics” under the direction “Equivalent test and measurement technology of materials on electromagnetic energy equipment under extreme conditions”. Rod-pinch-diode (RPD) is the most widely used load configuration for point projection flash X-ray radiography, whose performance is limited by the high impedance, low power density and incapability of multi-frame radiography. Therefore, in this proposal it is proposed that an electrical wire explosion plasma opening switch (POS) be introduced to lower the impedance and regulate the self-pinch behaviours of electron beam for a RPD that based on fast linear transformer driver (FLTD). Researches are to be conducted on a four-stage FLTD device (320 kV/ 800 kA), and the first step will be optimizing the POS parameters to generate point source of hard X-ray with dose >200 mR at 1 m distance, diameter < 0.5 mm, duration <30 ns, so as to achieve high quality flash radiography with temporal resolution < 1 μs and spatial resolution < 0.1 mm. On this basis, it will be explored the possibility of multi-operation of POS thus multi-pulse point source radiation of hard X-ray driven by multi-peak pulses with hundred ns to hundred μs time interval generated by timing the triggering of the four stages of the FLTD. The dynamics of POS plasmas and the self-pinching process of electron beams in the low-impedance RPD will be studied in detail with the assistance of high resolution laser imaging and MHD and particle simulation. The outcome of this project will provide basis for the construction of FLTD-based compact flash radiography devices, and will help the development of RPD-based multi-frame flash radiography technology.