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Diagnostics of density fluctuations by enhanced scattering with frequency-tunable microwave sources

  • O. Dumbrajs
  • J. A. Heikkinen
  • K. Sarparanta
  • S. K. Sipilä
  • K. Novik
  • A. Piliya
Article

Abstract

The enhanced scattering diagnostics method based on the scattering of microwaves close to the upper hybrid resonance in the plasma has a high sensitivity and spatial resolution and makes it possible to observe the plasma density fluctuations with characteristic scale-lengths much smaller than the wavelength of the probing radiation in vacuum. Good spatial resolution for spatial positioning of the scattering volume by fast tuning of the source frequency ±5% around the reference frequency in the range 100–300 GHz at high power makes this diagnostic method particularly suitable for fluctuation and high energy particle measurements in tokamak plasmas with relatively flat density and temperature profiles.

Key words

plasma diagnostics enhanced scattering gyrotron frequency tunability 

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References

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Copyright information

© Plenum Publishing Corporation 1995

Authors and Affiliations

  • O. Dumbrajs
    • 1
  • J. A. Heikkinen
    • 2
  • K. Sarparanta
    • 1
  • S. K. Sipilä
    • 1
  • K. Novik
    • 3
  • A. Piliya
    • 3
  1. 1.Department of Technical PhysicsHelsinki University of TechnologyEspooFinland
  2. 2.VTT EnergyVTTFinland
  3. 3.A. F. Ioffe Physico-Technical InstituteSt. PetersburgRussia

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