X射线荧光成像技术具有局域探测能力,适合诊断复杂几何构型流体运动,在实验室天体物理、惯性约束聚变等高能量密度物理领域具有重要的应用前景。基于神光Ⅲ原型激光装置,开展了X射线荧光成像的原理验证实验。实验采用聚4-甲基-1-戊烯泡沫掺杂TiO2纳米颗粒为静态客体,以钒等离子体辐射为荧光泵浦源,以平晶谱仪为分光和成像设备,成功获得了钛原子K壳层荧光的一维空间分辨强度轮廓。基于荧光产生和平晶成像原理,对荧光信号强度进行了定量估算,结果表明,模拟和实测荧光强度轮廓符合较好。该工作可为X射线荧光成像技术在复杂几何构型流体实验中的应用提供参考。

X-ray fluorescence imaging (XRFI) is a promising diagnostic method with respect to the geometrically complex fluids in high-energy-density physics, including experimental astrophysics and inertial confinement fusion, because of its capability of detecting localized information. In this study, we have conducted a proof-of-principle experiment with respect to XRFI at the Shenguang-Ⅲ prototype laser facility. In this experiment, a static object comprising poly-4-methyl-1-pentene foam and titanium dioxide nanoparticles was pumped with vanadium plasma radiation, resulting in the emission of titanium K-shell fluorescent photons. A flat-crystal spectrometer dispersed and imaged these fluorescent photons, and one-dimensional spatially resolved intensity profiles were successfully obtained. Further, the fluorescent intensity profiles were quantitatively simulated based on the theories related to fluorescence production and flat-crystal imaging, denoting good agreement with the experimental results. This research is directly useful for the application of XRFI to hydrodynamic experiments in case of complex geometries.