高分辨X射线晶体谱仪及其在激光等离子体中的应用

对椭圆型聚焦晶体谱仪配X射线CCD相机的X射线谱测量系统进行了优化设计.优化设计后的椭圆型聚焦晶体谱仪系统的工作距离981.56 mm和摄谱范围0.133～0.756nm,并具有很好的谱分辨本领(λ/Δλ≥1000)和信噪比.新设计的椭圆型聚焦晶体谱仪首次在"神光Ⅱ"X光激光靶室上成功地获得了激光等离子体谱线信息并辨认和归类了一些离子的谱线,同时还给出了实验测定的谱仪能量分辨率.其中一些离子谱线诸如类离子共振线、伴线、互组合线和Ly-α线谱可为下一步诊断激光等离子体的电子温度和离子密度的空间分布轮廓打下了坚实基础.

High-Resolution X-Ray Crystal Spectrometer and Its Application in Laser Plasmas

The elliptical bent crystal spectrometer (EBCS) is coupled to X-ray CCD, and a set of system called focusing spectrometer has been developed. Optimization calculation indicates that the EBCS will allow a large measuring spectral range (0.133～0.756 nm) with crystals of practical dimensions and for a working distance of 981.56 mm to the source and have a spectral resolving power (λ/Δλ) better than 1000 as well as high signal-noise-ratio. X-ray spectrum from the laser-produced plasma has first been measured by the EBCS in the “ShenGuang Ⅱ” Facility. Some ion-like spectral lines were identified and classified. The measured energy resolution of spectrograph was also given. Such emission of resonance line, satellite line inter-combination line of like ions, and Lyman alpha line is useful for establishing the spatial distribution of electron temperature and ions density maps.