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08:01
Spectral and Angle-Resolved Magneto-Optical Characterization of Photonic Nanostructures
Published on: November 21, 2019
Improved spectral analysis for the motional Stark effect diagnostic.
1Department of Physics, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA. jinseok@nfri.re.kr
The Review of Scientific Instruments
|November 7, 2012
Summary
Researchers improved magnetic field measurements in reversed field pinch plasmas using advanced spectral analysis. This enhances understanding of plasma behavior in fusion devices like the Madison Symmetric Torus (MST).
Area of Science:
- Plasma Physics
- Fusion Energy Research
- Magnetic Confinement
Background:
- Reversed Field Pinch (RFP) plasmas are crucial for fusion energy research.
- Accurate measurement of magnetic pitch angle and magnitude is essential for understanding RFP plasma dynamics.
- The Madison Symmetric Torus (MST) is a key facility for RFP research.
Purpose of the Study:
- To enhance the accuracy and reliability of magnetic pitch angle and magnitude measurements in MST plasmas.
- To refine the spectral analysis techniques for motional Stark effect (MSE) data.
- To improve the characterization of magnetic field structures in RFP devices.
Main Methods:
- Utilized fully resolved motional Stark effect (MSE) spectrum analyses.
- Implemented an improved spectrum fit procedure with MSE model-based initialization and constraints.
- Employed a collisional-radiative model with nlm-resolved level populations up to n = 4.
- Applied a simple Born approximation for ion-impact cross sections.
- Quantified measurement uncertainty using multi-view MSE measurements.
Main Results:
- The improved spectrum fit procedure enhances the accuracy of magnetic pitch angle and magnitude determination.
- Measurement uncertainties range from 5%-15% under typical MST operating conditions.
- Multi-view fitting significantly improves the goodness of fit for MSE spectral features and background noise.
Conclusions:
- The refined MSE analysis provides more reliable magnetic field data for RFP plasmas.
- Enhanced diagnostic capabilities contribute to a deeper understanding of plasma confinement and stability in MST.
- This work advances the tools necessary for future fusion energy development.
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