We discuss the effects of the ion distribution of a magnetically-enhanced Vacuum Arc Thruster using different cathode materials (Fe, Al, Cu) and magnetic field strengths. We develop a formalism, which is based on physical and geometric ideas, that describes the data for the inclusion of a magnetic field better than previous models (R > 0.89 for worst case). Our tests were performed on a Vacuum Arc Thruster with 270 A discharge current and an average pulse length of 3.5 ms. The magnetic field generator, driven by a separate capacitive discharge circuit, produced field strengths ranging from 0 to 250 mT along the thruster's centerline. We obtained the thrust correction factor and theoretical thrust from our measurements. It was found that application of magnetic fields increased ion density and axial momentum along the plasma plume's centerline. At higher magnetic field strengths (∼250 mT) the thrust factor decreased across all materials. For our electrodes, the inclusion of a protruding magnetic nozzle was seen to cancel the benefits arising from beam collimation due to the magnetic field. The iron electrode performed best, which may be due to its ferromagnetic nature.

中文翻译：

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所选阴极材料对磁力增强真空电弧推进器的影响

我们讨论了使用不同阴极材料（铁、铝、铜）和磁场强度的磁增强真空电弧推进器的离子分布的影响。我们开发了一种基于物理和几何思想的形式主义，它比以前的模型更好地描述了包含磁场的数据（最坏情况下 R > 0.89）。我们的测试是在放电电流为 270 A、平均脉冲长度为 3.5 毫秒的真空电弧推进器上进行的。磁场发生器由独立的电容放电电路驱动，沿推进器中心线产生 0 至 250 mT 的磁场强度。我们从测量中获得了推力修正系数和理论推力。研究发现，磁场的应用增加了离子密度和沿等离子体羽流中心线的轴向动量。在较高的磁场强度（~250 mT）下，所有材料的推力因子都会降低。对于我们的电极，包含突出的磁性喷嘴被认为抵消了磁场导致的光束准直带来的好处。铁电极表现最好，这可能是由于其铁磁性质。