Analysis of Magnetohydrodynamic Instabilities in TJ-II Plasmas
Analysis of Magnetohydrodynamic Instabilities in TJ-II Plasmas
复制标题
TJ-II 等离子体中磁流体动力学不稳定性分析
DOI：
10.13182/fst07-a1283
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发表时间：
2007
影响因子：
0.9
通讯作者：
D. Lopez
中科院分区：
文献类型：
--
作者：
R. Jiménez;E. Ascasíbar;T. Estrada;I. García;B. V. Van Milligen;A. López;I. Pastor;D. Lopez
摘要磁流体动力学不稳定性的TJ-II仿星器正在实验的特点是在各种等离子体参数制度和加热的情况下。使用分布在真空容器的不同环形扇区的各种Mirnov线圈组收集磁场波动数据，频率分辨率高达1 MHz。具体的分析进行了与信号从极向阵列的15个线圈测量极向磁场波动。在电子回旋加热等离子体中，低频模式（几十千赫）的出现取决于旋转变换轮廓和等离子体密度。在中性束注入等离子体中，在线密度在0.6 × 1019 m-3到3 × 1019 m-3范围内的等离子体中发现了高频（150- 300-kHz）模式，并通过轴上/离轴电子回旋加热来加热。它们是与低阶共振n/m = 3/2相关的全局Alfvén本征模的良好候选者。
Abstract Magnetohydrodynamic instabilities in the TJ-II stellarator are being experimentally characterized in various plasma parameter regimes and heating scenarios. Magnetic field fluctuations data are collected, using various Mirnov coil sets distributed at different toroidal sectors of the vacuum vessel, with frequency resolution up to 1 MHz. Specific analysis is carried out with the signals from a poloidal array of 15 coils measuring poloidal magnetic field fluctuations. The appearance of low-frequency modes (some tens of kilohertz) in electron cyclotron heated plasmas depends on the rotational transform profile and plasma density. In neutral beam injection plasmas, high-frequency (150- to 300-kHz) modes have been found in plasmas with line densities in the range 0.6 × 1019 m-3 to 3 × 1019 m-3 and heated with on/off-axis electron cyclotron heating. They are good candidates for global Alfvén eigenmodes related to the low-order resonance n/m = 3/2.