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Electron density and temperature profile diagnostics for C-2 field reversed configuration plasmas
B H Deng1, J S Kinley, J Schroeder
1Tri Alpha Energy, Inc., Rancho Santa Margarita, California 92688, USA. bdeng@trialphaenergy.com
The Review of Scientific Instruments
|November 7, 2012
Summary
Improved Thomson scattering diagnostics enhance electron temperature measurements in C-2 field reversed configuration plasmas. Plasma wobble motion aids in more accurate density profile reconstruction using interferometry.
Area of Science:
- Plasma Physics
- Fusion Energy Research
Background:
- The C-2 device utilizes field reversed configurations (FRCs) for fusion energy research.
- Accurate plasma diagnostics are crucial for understanding and controlling FRC stability and performance.
Purpose of the Study:
- To enhance the Thomson scattering diagnostic system for improved electron temperature measurements in C-2 FRC plasmas.
- To improve the accuracy of density profile reconstruction using interferometry data.
Main Methods:
- Upgraded a 9-point Thomson scattering diagnostic system.
- Utilized Rayleigh scattering to characterize laser emission line width.
- Employed plasma wobble motion to refine density profile reconstruction from CO(2)/HeNe interferometer data.
Main Results:
- Measured electron temperature profiles align with theoretical predictions.
- Identified a finite line width in ruby laser emission, impacting density calibration.
- Achieved improved accuracy in density profile reconstruction.
Conclusions:
- The enhanced Thomson scattering system provides reliable electron temperature data for C-2 FRC plasmas.
- Addressing laser line width effects is necessary for precise density measurements.
- Plasma wobble motion is a valuable technique for improving interferometric density diagnostics.
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