Design and Experimental Characterization of an Additively Manufactured Electrostatic Analyzer

Abstract

Electrostatic analyzers (ESAs) are charged-particle instruments central to space plasma physics, providing energy-per-charge resolved measurements of particle populations in the solar wind, planetary magnetospheres, and heliospheric boundaries. Conventional ESA fabrication relies on CNC machining, which can be costly, time-intensive, and poorly suited to rapid design iteration. This thesis investigates the use of Direct Metal Laser Sintering (DMLS), a metal additive manufacturing technique, as an alternative fabrication pathway for top-hat ESA prototyping. A top-hat ESA was designed from first principles, with geometric parameters selected to target an analyzer constant of approximately 4.5 and an energy resolution below 20% for 5 keV incident particles, incorporating constraints arising from DMLS manufacturing including minimum wall thickness requirements, high-voltage isolation, and ultra-high vacuum (UHV) compatibility. Electrostatic performance was predicted using SIMION particle trajectory simulations, yielding values for analyzer constant, energy resolution, geometric factor, and angular field of view. The fabricated analyzer underwent vacuum compatibility testing, high-voltage conditioning, and performance characterization using a 5 keV ion beam and a microchannel plate (MCP) detector. The measured analyzer constant of K ≈ 4.31 showed good agreement with both the theoretical value of 4.5 and the simulated value of approximately 4.0, while the experimental energy resolution of 15.7% was slightly wider than the simulated value of 12.6%, with the discrepancy attributed to particle scattering, surface roughness, and alignment uncertainties. DMLS-fabricated components demonstrated stable high-voltage operation and full UHV compatibility following standard cleaning and bakeout procedures. These results establish that additive metal manufacturing is a viable approach for ESA prototyping, offering geometric flexibility and rapid iteration while achieving performance comparable to conventionally machined instruments.