一种基于多普勒频移光谱的中性束注入器气体靶厚度诊断的新方法（英文）  

A New Diagnostic Technique for Gas Target Thickness Based on the Doppler Shift Spectroscopy on Neutral Beam Injector

作　　者：王艳[1,2] 刘智民[1,2] 焉镜洋 梁立振[1] 韦江龙 胡纯栋[1,2] WANG Yan;LIU Zhi-min;YAN Jing-yang;LIANG Li-zhen;WEI Jiang-long;HU Chun-dong(Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031, China;University of Science and Technology of China, Hefei 230026, China)

机构地区：[1]中国科学院等离子体物理研究所,安徽合肥230031 [2]中国科学技术大学,安徽合肥230026

出　　处：《光谱学与光谱分析》2018年第6期1987-1992,共6页Spectroscopy and Spectral Analysis

基　　金：the National Magnetic Confinement Fusion Science Program of China(2013GB101000);National Natural Science Foundation of China(1157240,1150224)

摘　　要：中性束注入是等离子体加热和电流驱动的最有效方法之一。中性束注入的三个基本过程为:离子束的产生,离子束的中性化和中性束的传输,其中,离子束的中性化是关键环节之一。对于EAST-NBI气体中性化室而言,中性化室内气体靶厚度会直接影响离子束的中性化效率,而且还会进一步影响到中性束的传输效率。基于多普勒频移效应,提出了一种新的诊断气体靶厚度的方法,并且已经被应用于EASTNBI测试平台上。该方法主要是基于中性束的束成分随气体靶厚度的演化过程,利用中性束发射Dα光谱线强度完成计算。因此,它被应用于中国科学院等离子体物理研究所EASTNBI装置上。在中性化室出口处的观测窗口上进行测量,在束能量为40～65keV时,气体靶厚度值为(0.16～0.22)×10^(16) cm^(-2),随着引出束流的变化,气体靶厚度随之改变。根据质量守恒定律,对中性化室内的气体靶厚度进行一个粗略的估算,估算的结果与测量的结果基本保持一致,从而证明了该诊断方法的合理性。综上,实验结果表明,该种基于多普勒频移效应的光谱诊断法可以被用于测量中性化室内的气体靶厚度。Neutral beam injection （NBI） is one of the most effective means of plasma heating and current driving. There are three basic processes in neutral beam injector： generation of ion beam,neutralization of ion beam and transmission of neutral beam, among which neutralization of ion beam is the key link. The gas target thickness in neutralizer directly affects the neutralization process, and further affects neutral beam transmission efficiency.A new diagnostic technique for the determination of gas target thickness, based on the Doppler shift effect, is presented and applied to neutral beam injector operating on Experimental Advanced Superconducting Tokamak （EAST） NBI testbed. The basis of the method is the process of beam component evolution with gas target thickness.The gas target thickness is estimated by the value of Dalpha spectral line intensity. The method is applied to the EAST NBI of Institute of Plasma physics, Chinese Academy of Sciences （ASIPP）. Gas target thickness in the range of 0.16~0.22×1016 cm-2 are measured close to the exit of neutralizer,and gas target thickness measured with this novel technique correlate very well with the extracted beam current. According to the law of conservation of mass, a rough calculation of gas target thickness is basically consistent with the calculation of the novel technique, which verifies its correctness. Experimental results show that spectrum method based on the Doppler shift effect can be applied to estimate neutralizer gas target thickness.

关 键 词：多普勒频移效应 中性束注入 气体靶厚度 

分 类 号：O433.4[机械工程—光学工程]