Demonstration of Field Emission Cathode Operation in a Plasma Environment
نویسندگان
چکیده
Field emission cathodes are being considered for use on low-power electrostatic and electromagnetic propulsion systems as well as on electrodynamic tether systems. In these systems, field emission cathodes prevent negative spacecraft charging by emitting a lowpower electron beam that is accommodated by the ambient plasma. Prototype cathodes were tested at the University of Michigan as part of a Student Space Systems Fabrication Laboratory satellite project. This paper presents experimental emission performance results of molybdenum and carbon nanotube field emission cathodes operating in a krypton plasma of density ne=1x10 m and temperature Te = 0.5 – 1.0 eV.
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