Microwave Interferometer in the Limiter Shadow (MILS) is a new diagnostic, installed on ASDEX Upgrade for electron density measurements in the far Scrape-Off Layer (SOL). At the chosen frequency of 47 GHz, the region of measurements varies within several centimetres before and after the limiter, depending on the density. 200 kHz bandwidth allows resolving transient events such as edge localized modes filaments and turbulence filaments. The measured quantities, phase shift, and power decay of the microwave beam, which crosses the plasma, are directly connected to the density and do not depend on any other plasma quantity. In this work, we analyse the influence of a filamentary perturbation on MILS signals. Simple representation of a filament is adopted, with parameters relevant to experimental filament properties, reported for ASDEX Upgrade. Forward modelling is done in COMSOL software by using RAPLICASOL, to study the response of the MILS synthetic diagnostic to the presence of a filament. Qualitative and quantitative dependencies are obtained and the boundaries of MILS sensitivity to filaments, or to the density perturbation in far SOL in general, are outlined.

中文翻译：

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限制器阴影中微波干涉仪对 ASDEX 升级中灯丝的灵敏度

限制器阴影中的微波干涉仪 (MILS) 是一种新诊断仪，安装在 ASDEX 升级版上，用于测量远刮除层 (SOL) 中的电子密度。在选定的 47 GHz 频率下，测量区域在限制器前后几厘米内变化，具体取决于密度。200 kHz 带宽允许解决瞬态事件，例如边缘局部模式细丝和湍流细丝。穿过等离子体的微束的测量量、相移和功率衰减与密度直接相关，不依赖于任何其他等离子体量。在这项工作中，我们分析了丝状扰动对 MILS 信号的影响。采用了灯丝的简单表示，并带有与实验灯丝特性相关的参数，为 ASDEX 升级报告。在 COMSOL 软件中使用 RAPLICASOL 进行正演建模，以研究 MILS 合成诊断对细丝存在的响应。获得了定性和定量的相关性，并概述了 MILS 对细丝或远 SOL 中的密度扰动的敏感性边界。