用X射线激光M-Z干涉仪诊断点聚焦CH等离子体电子密度

在神光Ⅱ装置上，用软X射线激光Mach-Zehnder干涉仪诊断了点聚焦CH等离子体电子密度N_e分布，介绍了实验结果. 通过Abel变换进行了密度反演， 给出了N_e的2D分布，测得的最高N_e为3.2×10²¹cm^-3. 通过同1.5维JB19程序以及二维XRL2D程序的模拟结果的比较，发现高密度区，限流因子取0.05的理论结果同实验相符，但是低密度区实验得到的N_e分布下降得更快，而且理论模拟的N_e二维分布同实验结果在细节上有比较大的差别. 粗略的误差分析显示，干涉仪面型误差是实验误差的主要来源. 关键词： 类镍银X射线激光 Mach-Zehnder干涉仪 密度反演 Abel变换

Diagnosis of electron density in spot-focused CH plasma with X-ray Laser M-Z interferometer

A soft X-ray laser Mach-Zehnder interferometer was used to diagnose electron density N_e of spot-focused CH plasma on Shengguang II facility, and the experimental results were presented in this paper. Density reconstruction was performed by making Abel transform, 2D distribution of N_e was obtained, and the highest N_e was about 3.2×10²¹cm^-3. Comparing with simulation results of JB19 code (1.5D) and XRL2D code (2D), it was found that the theoretical result with flux-limited factor of 0.05 agreed with reconstructed result in high density area, but experimental result gave an N_e distribution declining faster. Furthermore, 2D N_e distribution of simulation differed much from that of experiment in details. A brief error analysis showed that flatness error of interferometer dominated the experimental error.