Edge toroidal charge exchange spectra analysis in the EAST

Area of Science:

• Plasma physics
• Spectroscopy
• Fusion energy research

Background:

• The Experimental Advanced Superconducting Tokamak (EAST) utilizes edge toroidal charge exchange recombination spectroscopy (eCXRS) to measure edge plasma properties.
• Standard eCXRS analysis typically focuses on the carbon VI spectral line.

Purpose of the Study:

• To revise the spectral analysis for eCXRS on EAST to include spectral lines from other impurities.
• To improve the accuracy of eCXRS measurements by accounting for passive iron (Fe) lines originating from the ion cyclotron range of frequencies (ICRF) antenna.

Main Methods:

• Deployment of eCXRS diagnostic on the EAST tokamak.
• Identification and inclusion of passive Fe spectral lines within the 528 nm-530 nm wavelength range into the spectral analysis.
• Revision of the eCXRS spectral analysis algorithm.

Main Results:

• The revised spectral analysis successfully incorporates Fe spectral lines.
• The inclusion of Fe lines addresses spectral interferences in the 528 nm-530 nm range.
• Accuracy of eCXRS measurements was demonstrably improved.

Conclusions:

• A revised eCXRS spectral analysis, incorporating Fe lines, enhances measurement accuracy on EAST.
• This improved analysis provides more reliable data for edge plasma ion temperature and toroidal rotation.
• The method is crucial for accurate plasma diagnostics in fusion devices with similar setups.