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Updated: Jun 21, 2026
06:42
Magnetically Induced Rotating Rayleigh-Taylor Instability
Published on: March 3, 2017
Energetic-electron-driven instability in the helically symmetric experiment.
C B Deng1, D L Brower, B N Breizman
1Department of Physics and Astronomy, University of California, Los Angeles, Los Angeles, California 90095, USA.
Physical Review Letters
|August 8, 2009
Summary
Energetic electrons drive acoustic instabilities in quasi helically symmetric stellarators. Breaking symmetry eliminates these plasma core fluctuations, indicating a dependence on the device
Area of Science:
- Plasma physics
- Fusion energy research
- Stellarator dynamics
Background:
- Electron cyclotron resonance heating (ECRH) is a key technique for plasma heating in fusion devices.
- Understanding plasma instabilities is crucial for achieving stable fusion conditions.
Purpose of the Study:
- To investigate instabilities driven by energetic electrons in a quasi helically symmetric stellarator.
- To determine the nature and symmetry dependence of these plasma fluctuations.
Main Methods:
- Utilizing a quasi helically symmetric stellarator device.
- Employing electron cyclotron resonance heating (ECRH) to generate energetic electrons.
- Measuring plasma fluctuations using diagnostic tools to analyze frequency and propagation.
Main Results:
- Observed coherent, global fluctuations in the plasma core (20-120 kHz).
- Mode propagation aligned with the diamagnetic drift direction of energetic electrons.
- Instability was absent when quasihelical symmetry was broken.
Conclusions:
- Energetic electrons can drive acoustic instabilities in quasi helically symmetric stellarators.
- Quasihelical symmetry is essential for the existence of these specific instabilities.
- The findings contribute to understanding plasma behavior in stellarator devices.
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