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Compact High Current Rare-Earth Emitter Hollow Cathode for Hall Effect ThrustersAn apparatus and method for achieving an efficient central cathode in a Hall effect thruster is disclosed. A hollow insert disposed inside the end of a hollow conductive cathode comprises a rare-earth element and energized to emit electrons from an inner surface. The cathode employs an end opening having an area at least as large as the internal cross sectional area of the rare earth insert to enhance throughput from the cathode end. In addition, the cathode employs a high aspect ratio geometry based on the cathode length to width which mitigates heat transfer from the end. A gas flow through the cathode and insert may be impinged by the emitted electrons to yield a plasma. One or more optional auxiliary gas feeds may also be employed between the cathode and keeper wall and external to the keeper near the outlet.
Document ID
20120003730
Acquisition Source
Headquarters
Document Type
Other - Patent
Authors
Hofer, Richard R.
Goebel, Dan M.
Watkins, Ronnie M.
Date Acquired
August 25, 2013
Publication Date
March 27, 2012
Subject Category
Spacecraft Propulsion And Power
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.
Patent
US-Patent-8,143,788
Patent Application
US-Patent-Appl-SN-12/202,252
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