数千电子伏特(Multi-keV)量级的X射线背光成像是高能密度等离子体物理实验中常用的一种诊断技术。在神光II激光装置上, 研究了纳秒激光驱动钛4.7 keV波段及氯2.7 keV波段背光面源的性能。研究结果表明, 氯背光能谱以类He线及类H线为主, 其中2.7 keV波段的类He-α线最强; 在当前神光II激光加载能力下, 氯背光面源相对强度超过钛背光面源一个量级, 因此, 可选用氯He-α线的X光探针进行背光诊断。

Multi-keV X-rays are used as backlighting sources of the radiography to diagnose plasmas in high energy density physics (HEDP) experiments. We study the characteristics of Ti-4.7 keV and Cl-2.7 keV X-rays driven by nanosecond laser at the SG-II laser facility. The results show that the X-rays from Cl plasma are primarily He-like and H-like line radiation, with 2.7 keV He-α line on the strongest line emission. In addition, the relative intensity of Cl X-rays is more than an order of magnitude compared to that of Ti X-rays under the current SG-II laser conditions. Therefore, the Cl X-rays can be used as the backlighting diagnosis.