Fluctuation in a Helicon plasma with additional immersed antenna

Res. Sch. of Phys. Sci. & Eng., Australian Nat. Univ., Canberra, ACT, Australia
IEEE Transactions on Plasma Science (Impact Factor: 1.1). 05/2005; 33(2):360 - 361. DOI: 10.1109/TPS.2005.845133
Source: IEEE Xplore

ABSTRACT Fluctuations in the floating potential are measured in a cylindrical magnetised plasma, as the phase between a "primary" Helicon antenna and a "secondary" immersed antenna is varied. The two antennas are powered by separate radio frequency (RF) generators of 13.56 MHz controlled by a single oscillator and phase shifter. The Helicon antenna is separated from the plasma by a glass tube, while the immersed copper antenna is in direct contact with the plasma. The image presented here shows floating potential fluctuations of ∼100 Hz where the amplitude of the fluctuations vary dramatically with the phase between the two RF generators.

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Available from: Åshild Fredriksen, Oct 16, 2012
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