Compact ion beam source for feedback control of plasma instabilities
- Plasma Physics Laboratory, Columbia University, New York, New York 10027 (United States)
A compact ion beam source has been constructed for use in the Columbia Linear Machine for feedback control of plasma instabilities. This source has been used in a feedback configuration to stabilize the collisionless trapped particle instability (Phys. Rev. Lett. {bold 67}, 204 (1991)). The source was based on an {bold E}{times}{bold B} hot cathode, magnetron-type design. It utilized the background magnetic field and a radial discharge voltage to obtain the azimuthal {bold E}{times}{bold B} drifts. The pressure inside the discharge chamber was maintained in the mTorr range via differential pumping. The source had a stable operating window in gas pressure of over 50% about the chosen operating parameters. Typical source plasma parameters were a plasma potential of 100 V, an electron temperature of 10 eV, and a plasma density of 10{sup 9}--10{sup 10} cm{sup {minus}3}. The power dissipated was around 30 W. The ion beam energy was typically 100 eV with an energy spread of 20 eV and it could be modulated 100%. In addition, external control of the ion beam energy was provided via the anode bias.
- DOE Contract Number:
- FG02-87ER53257
- OSTI ID:
- 7154005
- Journal Information:
- Review of Scientific Instruments; (United States), Vol. 63:10; ISSN 0034-6748
- Country of Publication:
- United States
- Language:
- English
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