Source tracing and diagnostic analysis of carbon erosion contaminants in hall thrusters based on spatiotemporal matrix-synchronized spectroscopy technology

Abstract

Current research based on quartz crystal microbalance (QCM) measurements and theoretical simulations suggests that the carbon erosion contaminants observed in Hall thruster ground testing originates from the vacuum system walls and the magnetic poles of the Hall thruster. However, since QCM lack species discrimination capability, preventing direct validation of simulations and creating a gap in carbon source identification. To address this, this work employs optical emission spectroscopy, and develops a spatiotemporal matrix-synchronized spectroscopy technique. By acquiring real-time spatial distribution of carbon atoms, four distinct spatial distribution patterns were observed, indicating that the carbon source cannot be determined solely by spatial orientation. Further comparative analysis of carbon and boron spatial distributions revealed that carbon and boron share the same origin, confirming that the carbon stem from inner magnetic pole sputtering rather than vacuum system walls in this work. Using spatiotemporal matrix-synchronized spectroscopy monitoring system, this work obtained carbon atom spatial distribution data with temporal sequencing. This approach facilitates the online monitoring of erosion and transport evolution trends during Hall thruster wearing tests. By developing spatiotemporal matrix-synchronized spectroscopy, this work achieves source tracing of carbon erosion products, offering direct experimental data for analyzing wall effects in Hall thrusters and refining erosion-transport models.