激光等离子体类氖GeX射线吸收谱研究

X-RAY ABSORPTION SPECTROSCOPY OF NEON - LIKE GERMANIUM INOS IN LASER-PRODUCED PLASMAS

摘要: 在国际上首次进行了空间分辨的激光等离子体类氖GcX射线吸收谱研究.实验在高功率激光物理联合实验室的神光六路装置上进行,采用新颖的"点投影(pointprojection)"吸收谱方案,研究了激光脉冲峰值以后200ps时刻Ge等离子体中类氖离子密度的空间分布特性(空间分辨约24μm),结果获得了类氖Ge2p-3d的共振吸收谐信号。实验结果同国内一维流体力学JB19编码的模拟结果进行了比较。

Abstract: In this work we have developed and successfully demonstrated the“point projec-tion absorption spectroscopy(PPAS)’technique to record keV absorption spectra in coronalregions of laser produced germanium plasmas which provides spatial information in coronas withnresolusion of～24μm and can freeze the motion of the expanding plasmas at the ≈ 25ps level.The 1-D hydrocode JB19 have been used to simulate the experiment in plannar geometry over arange of intensity,and the predictions are compared to the observations.Such comparison can beuseful in validating parts of the codes used for gain predictions of soft X-ray laser transitions.