Spectral characterization of an educational Hall Effect Thruster

An SPT-type Hall Effect Thruster was built by a team of students form several MA colleges [1]. Test operation on Ar and Kr propellants was recently attempted at the Northeastern University Plasma Laboratory. HET was mounted inside the 10 m³ vacuum chamber with ~10,000 L/s pumping capacity using the infrastructure developed for the BHT-200 [2,3]. Broad NUV-NIR spectra were collected for both propellants. They reveal the presence of neutral atoms, ions, and diatomic molecules. Doppler spectroscopy of a strong Kr ion emission line was attempted using the high-resolution system for non-invasive plasma diagnostics [4]. The collected Ar/Kr data and their analysis will be presented and discussed.