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Bismuth is the heaviest of all stable atomic isotopes. This property, combined with its relative abundance, low cost, and low ionization potential, makes bismuth a uniquely efficient propellant option for plasma-based propulsion devices. The first bismuth-fueled Hall thrusters were developed in Russia several decades ago, and there has been renewed interest in developing high powered bismuth Hall thrusters for future Nuclear Electric Propulsion missions to the outer planets of the solar system.
With this new interest, and the possible development of a new bismuth-fed thruster, comes the need to perform diagnostics on such a thruster. To aid in the development of these diagnostics, a laboratory-model linear Hall thruster has been modified to run on bismuth propellant. This thruster provides a test bed for diagnostic development while more advanced bismuth thrusters are designed and developed. This thruster, along with other bismuth plasma sources developed in the Stanford Plasma Physics Laboratory, allows for analysis of the bismuth plasma in terms of spectroscopic emission, Laser Induced Fluorescence spectroscopy, and Atomic Resonance Absorption Spectroscopy. The ultimate goal of these diagnostics will be the measurement of the density and velocity field of neutral and ionized Bismuth in the Hall thruster plume. Work in this field leverages some previous techniques used on xenon-fed thrusters, working to adapt those methods to the particulars of the bismuth spectrum and to overcome several experimental difficulties that are unique to the bismuth propellant.
Hall Thruster Experiments
Bismuth Hall Thruster Experiments - Related Papers
Bismuth is the heaviest of all stable atomic isotopes. This property, combined with its relative abundance, low cost, and low ionization potential, makes bismuth a uniquely efficient propellant option for plasma-based propulsion devices. The first bismuth-fueled Hall thrusters were developed in Russia several decades ago, and there has been renewed interest in developing high powered bismuth Hall thrusters for future Nuclear Electric Propulsion missions to the outer planets of the solar system.
With this new interest, and the possible development of a new bismuth-fed thruster, comes the need to perform diagnostics on such a thruster. To aid in the development of these diagnostics, a laboratory-model linear Hall thruster has been modified to run on bismuth propellant. This thruster provides a test bed for diagnostic development while more advanced bismuth thrusters are designed and developed. This thruster, along with other bismuth plasma sources developed in the Stanford Plasma Physics Laboratory, allows for analysis of the bismuth plasma in terms of spectroscopic emission, Laser Induced Fluorescence spectroscopy, and Atomic Resonance Absorption Spectroscopy. The ultimate goal of these diagnostics will be the measurement of the density and velocity field of neutral and ionized Bismuth in the Hall thruster plume. Work in this field leverages some previous techniques used on xenon-fed thrusters, working to adapt those methods to the particulars of the bismuth spectrum and to overcome several experimental difficulties that are unique to the bismuth propellant.