Experimental Investigation of Helical Non‐neutral Plasmas
Experimental Investigation of Helical Non‐neutral Plasmas
复制标题
螺旋非中性等离子体的实验研究
DOI：
10.1063/1.1635189
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发表时间：
2003
期刊：
影响因子：
--
通讯作者：
M. Fukao
中科院分区：
文献类型：
--
作者：
H. Himura;H. Wakabayashi;M. Fukao
首次在紧凑螺旋系统（CHS）装置上对螺旋非中性等离子体进行了实验研究。(1)值得注意的是，尽管从封闭的磁性表面的外部发射，注入的电子穿过磁场并深入磁性表面内部。电子的这种穿透是由一种无碰撞的机制引起的，这种机制在过去被限制在轴对称几何形状中的环形非中性等离子体中从未观察到。(2)穿透的电子在磁表面内形成螺旋形非中性等离子体。电子密度约为1011-13 m−3，远小于布里渊密度极限。(3)螺旋形非中性等离子体的稳定阶段仅持续1 - 4 ms，然后开始中断。观察到约50 kHz的破坏性不稳定性。该频率和与不稳定性开始时间相关的其他参数表明离子相关的不稳定性是可能的机制。
For the first time, an experimental study on helical nonneutral plasmas is performed on the Compact Helical System (CHS) device. (1) Remarkably, despite being launched from the outside of closed magnetic surface, the injected electrons travel across the magnetic field and penetrate deeply inside the magnetic surfaces. This penetration of electrons is caused by a collisionless mechanism that has never been observed in past toroidal nonneutral plasmas confined in axisymmetric geometry. (2) The penetrated electrons form a helical non‐neutral plasma inside the magnetic surface. The electron density is about 1011–13 m−3 much smaller than the Brillouin density limit. (3) The stable phase of the helical non‐neutral plasma continues only for 1 – 4 ms and then starts to disrupt. About 50 kHz of disruptive instability is observed. This frequency and the other parameters related to the onset time of the instability suggest an ion‐related instability as the possible mechanism.