托卡马克等离子体杂质密度的光谱法测量研究

摘要

Background: Impurity density measurement is very important in tokamak plasma, especially for impurity behavior and transport study.Purpose:This study aims to obtain the impurity density of tokamak plasma by using passive spectroscopy diagnostics.Methods: Line emissions of impurity are measured by passive spectroscopy diagnostics, and the chord-integrated brightness profiles are obtained by multiplying the sensitivity calibration coefficients. The radial emissivity profiles corresponding to a certain number of considered magnetic surfaces can be obtained by using the version technique. Then the density profiles of impurity ions can be acquired according to the relationship of emissivity profiles and density profiles of impurity ions. And the total impurity density distribution can be calculated by the simulation of impurity transport code.Results: Experimental results on obtaining of total molybdenum density on experimental advanced superconducting tokamak (EAST) by soft X-ray and extreme ultraviolet spectrometers (XEUV) show the total measureing error is less than 10%.Conclusion: Impurity density can be measured by using spectroscopic method, combining spectroscopy diagnostics and impurity transport code.%本文介绍了基于托卡马克等离子体被动光谱诊断获得杂质密度的方法.通过被动光谱诊断测量获得杂质线辐射的空间多道弦积分强度分布,利用强度标定系数转换为绝对光亮度分布;通过测量弦与等离子体位形,将弦积分的强度分布反演变换为径向体发射率.根据线辐射强度激发截面求出对应电离态的离子密度,最后采用杂质输运程序模拟计算得出总密度分布.以东方超环(Experimental Advanced Superconducting Tokamak, EAST)托卡马克装置上软X射线-极紫外光谱(Soft X-ray and Extreme Ultraviolet Spectrometers, XEUV)诊断测量到的Mo XXIX?Mo XXXII为例,描叙了获得Mo杂质密度分布的过程,获得的总误差小于10%.