A magnetized plasma thruster variant with a divergent chamber and strong magnetic cusps has been been prototyped and preliminarily characterized at the MIT Space Propulsion Laboratory. This paper expands upon the previous work with a non-invasive, optical examination of the near-field plume and discharge chamber phenomena. Calibrated broadband spectra reveal changes in Xe I and II level populations with operational mode, while high resolution narrow bandwidth scans are used to examine trends in

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... multiply charged ion fractions and Doppler shifted profiles. An internal electrostatic probe apparatus is also decribed which has been installed to observe ion flux to diverging channel surfaces in order to determine the efficacy with which the magnetic topology is used to reduce ion bombardment energies. * Graduate Student, AIAA Student Member. † MIT Affiliate, Senior AIAA Member.