Kaur M, Diallo A, LeBlanc B, Segado-Fernandez J, Viezzer E, Huxford R B, Mancini A, Cruz-Zabala D J, Podesta M, Berkery J W, Garcia-Muñoz M
Princeton Plasma Physics Laboratory, Princeton, New Jersey 08540, USA.
Department of Atomic, Molecular and Nuclear Physics, University of Seville, Seville, Spain.
Rev Sci Instrum. 2024 Sep 1;95(9). doi: 10.1063/5.0219308.
We describe the design of a Thomson scattering (TS) diagnostic to be used on the SMall Aspect Ratio Tokamak (SMART). SMART is a spherical tokamak being commissioned in Spain that aims to explore positive triangularity and negative triangularity plasma scenarios at a low aspect ratio. The SMART TS diagnostic is designed to operate at high spatial resolution, 6 mm scattering length in the low-field side and 9 mm in the high-field side regions, and a wide dynamic range, electron temperature from 1 eV to 1 keV and density from 5×1018m-3 to 1×1020m-3, to resolve large gradients formed at the plasma edge and in the scrape-off layer (SOL) under different triangularities and low aspect ratios. A 2 J @1064 nm laser will be used that is capable of operating in the burst mode at 1, 2, and 4 kHz to investigate fast phenomena and at 30 Hz to study 1 s (or more) long discharges. The scattered light will be collected over an angular range of 60° - 120° from 28 spatial points in the midplane covering the entire plasma width and the outer midplane SOL. Each scattering signal will be spectrally resolved on five wavelength channels of a polychromator to obtain the electron temperature measurement. We will also present a method to monitor in situ laser alignment in the core during calibrations and plasma operations.
我们描述了一种将用于小径比托卡马克（SMART）装置的汤姆逊散射（TS）诊断系统的设计。SMART是一台正在西班牙调试的球形托卡马克装置，旨在探索低径比下的正三角形和负三角形等离子体工况。SMART的TS诊断系统设计用于在高空间分辨率下运行，低场侧散射长度为6毫米，高场侧区域为9毫米，并且具有宽动态范围，电子温度范围从1电子伏特到1千电子伏特，密度范围从5×10¹⁸立方米⁻³到1×10²⁰立方米⁻³，以分辨在不同三角形系数和低径比条件下等离子体边缘和刮离层（SOL）形成的大梯度。将使用一台能量为2焦耳、波长为1064纳米的激光器，它能够以1千赫兹、2千赫兹和4千赫兹的脉冲模式运行来研究快速现象，以30赫兹的频率运行来研究持续1秒（或更长时间）的长脉冲放电。散射光将在中平面内28个空间点上，从60° - 120°的角度范围内收集，覆盖整个等离子体宽度和外部中平面SOL。每个散射信号将在多色仪的五个波长通道上进行光谱分辨，以获得电子温度测量值。我们还将介绍一种在校准和等离子体运行期间原位监测核心区域激光对准的方法。
