“Electrodeless” Plasma Cathode for Neutralization of Ion Thrusters
نویسندگان
چکیده
Significant progress has been made in the characterization of the necessary parameters required to create an effective Radio Frequency (RF) plasma based electron source. Such a device has the promise of comparable current densities to and longer operational lifetimes than hollow cathodes. The operational lifetime of hollow cathodes is ultimately limited by cathode deterioration. RF sources provide an alternative approach that does not consume electrode material while providing electrons. Preliminary experiments suggest that an electron current of 3.75 Amps was extracted through an electron sheath near a grounded ring within an argon plasma using 340W of RF power. Permanent magnets provided an axial magnet field of 150 Gauss at the antenna. Experimental evidence from the RF plasma cathode suggests that the amount of neutralizing electron current that can be extracted is equal to the random electron flux and is limited by the plasma density, the neutral argon flow rate, and the ion loss area provided in the source.
منابع مشابه
The Use of Electrostatic Probes to Characterize the Discharge Plasma Structure and Identify Discharge Cathode Erosion Mechanisms in Ring-Cusp Ion Thrusters
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