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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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Attitude and orbit control electric propulsion systems for long term space stations, discussing resistojets and electron bombardment and contact ionization ion thrustors
Emitter applies to devices in which a plasma is generated by electron bombardment. Device is conventional hollow cathode modified by addition of integral keeper cap containing small aperture which encloses outlet of the cathode and is held in position by ceramic tube.
Effects of backsputtered material on performance of glass coated accelerator grids for electron bombardment thrusters
Electron bombardment ion rocket engine with improved propellant introduction system
Effects of mercury electron bombardment ion thruster exhaust products on surfaces located downstream
Electron paramagnetic resonance detection of electron bombarded lithium fluoride
Electronic cathodes for use in electron bombardment ion thrustors
Preliminary investigation to eliminate or reduce concentrated charge exchange ion erosion of accelerator grid supports for electron bombardment ion thrustors
Optimization of mercury electron bombardment thrusters in SERT program
Mercury vapor fed hollow cathodes for electron bombardment ion thrusters
Beam focusing characteristics of variously shaped grid holes with application to electron bombardment ion thrustors
Facility backsputtered material effect on performance of glass-coated accelerator grids for Kaufman electron bombardment thrusters
SERT II electron bombardment thruster operation with Ar and Hg propellants
Electron bombardment ion thrustor using hollow cathode and two-grid ion accelerating geometry, discussing performance tests
Electron bombardment mercury ion thrustor plasma properties and performance, computing ion beam current, discharge losses and propellant utilization efficiency
An experimental study of the effects of various modifications to the hollow cathode discharge region of a 20 cm electron bombardment ion thruster is presented. The introduction of electrical insulation between the main and cathode discharge regions is shown to have no significant effect on thruster performance. Adjustment of both the diameter and length of the cathode discharge region from the design condition are examined and the reduced sizes are shown to effect large improvements in propellant utilization when the thruster is operating at about 30% of the design thrust level. Performance improvements are shown to be less significant at higher thrust levels. The feasibility of using a high voltage tickler electrode to initiate the cathode-keeper discharge is considered and results obtained suggest this mode of startup is unsatisfactory.
Upper-limit charge exchange cross sections are calculated for Hg(+) on Mo and Cs(+) on Al. The cross sections are calculated from the polarization interaction at low ion energies (1 to 500 eV) and by assuming favorable curve crossings with a hard-core reaction radius at higher energies (500 eV to 10 keV). The cross sections for Hg(+) on Mo becomes greater than corresponding Hg Hg(+) resonance values at ion energies below 2 eV, whereas the Cs(+) Al values remain considerably lower than the Cs(+)Cs resonance value at all ion energies. It is also shown that charge exchange of slow Hg(+) with Mo may be important for spacecraft with electron bombardment thrusters.
The current status of research programs on mercury electron bombardment thrusters is reviewed. Future thruster requirements predicted from mission analysis are briefly discussed to establish the relationship with present programs. Thrusters ranging in size from 5 to 150 cm diameter are described. These thrusters have possible near to far term applications extending from stationkeeping to primary propulsion. Beam currents range from 10 mA at to 25 A at accelerating potentials of 500 to 5000 V.