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Rotation characteristics during the resonant magnetic perturbation induced edge localized mode suppression on the
The Review of Scientific Instruments
|November 29, 2014
Summary
Magnetic perturbations in KSTAR experiments suppress edge localized modes (ELMs) and reduce toroidal rotation. Rotation profiles collapse after ELM bursts and rebuild, with reduced rotation observed during ELM suppression.
Area of Science:
- Plasma physics
- Fusion energy research
- Edge plasma diagnostics
Background:
- Understanding plasma behavior, particularly edge transport, requires accurate rotation profile measurements.
- KSTAR experiments show magnetic perturbations suppress edge localized modes (ELMs) and reduce toroidal rotation.
Purpose of the Study:
- To present toroidal velocities of carbon impurities and their profile evolution during ELMy and ELM-suppressed phases.
- To investigate the impact of magnetic perturbations on plasma rotation.
Main Methods:
- Charge exchange spectroscopy measurements on KSTAR.
- Analysis of toroidal rotation profiles for carbon impurities.
Main Results:
- Rotation profiles collapse immediately after an ELM burst.
- Profiles rebuild until the next ELM burst.
- Toroidal rotations are reduced when ELMs are suppressed by resonant magnetic perturbations.
Conclusions:
- Magnetic perturbations effectively suppress ELMs and reduce toroidal plasma rotation.
- ELM activity significantly impacts rotation profile dynamics.
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