Feasibility study for a new high resolution Thomson scattering system for the ASDEX Upgrade pedestal
Feasibility study for a new high resolution Thomson scattering system for the ASDEX Upgrade pedestal
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用于 ASDEX 升级基座的新型高分辨率汤姆逊散射系统的可行性研究
DOI：
10.1088/1748-0221/7/03/c03015
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发表时间：
2012
影响因子：
1.3
通讯作者：
the ASDEX Upgrade Team
中科院分区：
文献类型：
--
作者：
M. Tsalas;M Yu Kantor;O. Maj;R. Bilato;P C de Vries;A. Donné;A. Herrmann;B. Kurzan;E. Wolfrum;the ASDEX Upgrade Team
提出了一种新的汤姆逊散射诊断方法，用于ASDEX升级装置基座快等离子体动力学的研究。诊断将测量电子温度和密度分布在一个约3厘米宽的区域在边缘传输势垒区，与~ 1？2 mm空间分辨率和~ 10 kHz采样率。该项目的一个具有挑战性的目标是通过测量电子分布沿着环向的畸变和偏移来研究等离子体基座中的自举电流。电流密度测量的预期空间和时间分辨率分别为~ 3 mm和~ 1 ms。新的诊断将用于研究基座自举电流的快速动态行为，模型表明它在调节边缘稳定性方面起着关键作用，例如在ELMs期间。诊断设计是基于TEXTOR目前运行的腔内多通系统，该系统使用探测红宝石激光器，光栅光谱仪和两个快速CMOS相机进行散射光检测，并已实现约1%的Ne和约2%的Te的测量精度。该系统的一部分将在ASDEX升级中重复使用（其中一些进行了重大修改），但激光多通道和光收集系统将完全重新设计。空间和视线可用性方面的限制导致采用了一种使用船内多通镜和光收集光学器件的设计，需要许多创新的技术解决方案来实现远程激光对准和光收集。我们给出了该项目的概述，讨论了潜在的物理基础，并提出了一些技术解决方案。
A new Thomson scattering diagnostic is proposed for the study of fast plasma dynamics in the pedestal of ASDEX Upgrade. The diagnostic will measure electron temperature and density profiles over a ~ 3 cm wide area in the edge transport barrier region, with ~ 1?2 mm spatial resolution and ~ 10 kHz sampling rate. A challenging goal of the project is the study of the bootstrap current in the plasma pedestal by measuring the distortion and shift of the electron distribution along the toroidal direction. Expected spatial and time resolutions of the current density measurements are ~ 3 mm and ~ 1 ms correspondingly. The new diagnostic will be used to study the fast dynamic behaviour of the pedestal bootstrap current, where models indicate that it plays a key role in regulating edge stability, e.g. during ELMs. The diagnostic design is based on the intra-cavity multi-pass system currently in operation in TEXTOR, which uses a probing ruby laser, a grating spectrometer and two fast CMOS cameras for scattered light detection, and has achieved measuring accuracies of the order of ~ 1% for ne and ~ 2% for Te. Parts of that system will be reused in ASDEX Upgrade (some with significant modifications), but the laser multi-pass and light collection systems are entirely redesigned. Restrictions in space and line-of-sight availability have led to the adoption of a design which uses in-vessel multi-pass mirrors and light collection optics, requiring a number of innovative technical solutions to permit remote laser alignment and light collection. We give an overview of the project, discuss the underlying physics basis and present a number of technical solutions employed.