Ko Jinseok
Korea Institute of Fusion Energy, Daejeon 34133, Korea.
Rev Sci Instrum. 2022 Aug 1;93(8):083503. doi: 10.1063/5.0101482.
The motional Stark effect (MSE) diagnostic system at KSTAR (Korea Superconducting Tokamak Advanced Research) often suffers from the drawback of possible systematic uncertainties in measurements due to overlap of the MSE spectra generated from three different ion sources that constitute a single neutral beam injection system. In particular, one ion source injected in the most tangential direction always causes strong spectral overlaps which, therefore, imposes regulations and constraints on the energy combination among the ion sources. A Stokes-vector analysis has been performed to produce operation windows for the energy combination between the ion source used in the MSE measurement and the ion source with the largest tangential injection angle. The analysis includes various practical factors, such as the distortion of the transmission function of bandpass filters and pitch angle profiles collected from a vast amount of KSTAR discharges. The two-dimensional parameter space, or the contour plot, on the expected systematic offsets in the measured pitch angle has been generated from this analysis, which can serve as a quantitative guideline for operating the multiple-ion-source neutral beam heating system.
韩国超导托卡马克先进研究装置（KSTAR）上的运动斯塔克效应（MSE）诊断系统经常存在一个缺陷，即由于构成单个中性束注入系统的三个不同离子源产生的MSE光谱重叠，测量中可能存在系统不确定性。特别是，以最切向方向注入的一个离子源总是会导致强烈的光谱重叠，因此，这对离子源之间的能量组合施加了规则和限制。已经进行了斯托克斯矢量分析，以生成MSE测量中使用的离子源与切向注入角度最大的离子源之间能量组合的操作窗口。该分析包括各种实际因素，如带通滤波器传输函数的失真以及从大量KSTAR放电中收集的俯仰角分布。通过该分析生成了测量俯仰角中预期系统偏移的二维参数空间或等高线图，它可以作为操作多离子源中性束加热系统的定量指南。
