论文标题
磁过滤场拓扑对Elise测试设施的梁发散的影响
Influence of the magnetic filter field topology on the beam divergence at the ELISE test facility
论文作者
论文摘要
Elise测试设施设有一个RF负离子源，配备了一个萃取系统，该系统应为ITER中性束注射器提供一半的预测，使得共提取电子与1以下的离子的比率。抑制共截图的磁性过滤器的重要工具是由磁性脱位的磁性过滤器，该磁场是由plass Mystraction the Periven extraction the Plas Mystraction in Plasma Grid of Privent extraction the Perivan extraction。为了提高源表现的磁性滤波场的生产新概念，已经测试了现有系统与附着在源壁上的永久磁铁。这些新的磁性构型的拓扑影响会影响提取区域中的梁颗粒轨迹，这对整体梁光学元件产生了影响。这些效果将在本文中通过研究束发射光谱（BES）诊断测量的梁颗粒的角度分布来表征。还将通过在接地网格上（第三个网格）以及其出口周围的网格支架盒上流动的电流的测量来研究梁的行为。主要发现是，当磁场通过永久磁体增强时，梁的更宽成分会增加，即，在大多数共摘取的电子被抑制的情况下。
The ELISE test facility hosts a RF negative ion source, equipped with an extraction system which should deliver half the current foreseen for the ITER Neutral Beam Injector, keeping the ratio of co-extracted electrons to ions below 1. An important tool for the suppression of the co-extracted electrons is the magnetic filter field, produced by a current flowing in the plasma grid, the first grid of the 3 stage extraction system. To boost the source performances new concepts for the production of the magnetic filter field have been tested, combining the existing system with permanent magnets attached on the source walls. The topologies of these new magnetic configurations influence the beam particles trajectories in the extraction region, with consequences for the overall beam optics. These effects will be characterized in this article by studying the angular distribution of the beam particles, as measured by the Beam Emission Spectroscopy (BES) diagnostic. The behavior of the beam will be studied also through the measurements of the currents flowing on the grounded grid (the third grid) and on the grid holder box surrounding its exit. The main finding is that the broader component of the beam increases when the magnetic field is strengthened by permanent magnets, i.e. in the cases in which most of the co-extracted electrons are suppressed.
