An automated plume diagnostic system is presented for two-dimensional mapping of the ion beam produced by using miniaturized electric propulsion devices. The instrument is designed to operate with noble and reactive gases and consists of a semi-circular probe array with a unique angular distribution following a Gaussian shape for improved beam profile resolution. To demonstrate the operation of the diagnostic system, a series of experiments are conducted with a low-power gridded ion thruster using xenon and iodine propellants. The two-dimensional current density maps generated are used to calculate important beam properties for performance estimates, including the total ion current and the effective divergence angle, and we show how the measurements can be used to assess and optimize the design of ion optics for gridded ion thrusters. All current density measurements with the new instrument are corrected for secondary electron emission (SEE) due to ion bombardment, and using a separate, specially designed, electrostatic probe, we present the first measurements of the SEE yield for iodine ions impacting molybdenum and SAE 304 stainless steel surfaces.

中文翻译：

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用于评估小型化电力推进系统的离子束诊断

提出了一种自动羽流诊断系统，用于对使用小型化电力推进装置产生的离子束进行二维映射。该仪器设计用于处理惰性气体和反应气体，由一个半圆形探头阵列组成，该阵列具有独特的角度分布，遵循高斯形状，以提高光束轮廓分辨率。为了演示诊断系统的操作，使用氙气和碘推进剂的低功率网格离子推进器进行了一系列实验。生成的二维电流密度图用于计算性能估计的重要光束属性，包括总离子电流和有效发散角，我们展示了如何使用测量来评估和优化网格化离子光学器件的设计。离子推进器。