Fast-ion D_α spectrum diagnostic in the EAST

Area of Science:

• Plasma Physics
• Fusion Energy Research
• Spectroscopy

Background:

• Fast-ion D-alpha diagnostic (FIDA) is crucial for studying fast-ion behavior in toroidal magnetic fusion devices.
• Fast-ion characteristics are inferred from Doppler-shifted Dα light spectra via charge exchange recombination.
• Previous conceptual designs have been advanced for FIDA application on the Experimental Advanced Superconducting Tokamak (EAST).

Purpose of the Study:

• To detail the significant progress in applying FIDA systems on the EAST.
• To present the hardware descriptions and experimental spectra of the newly installed FIDA systems.
• To enable simultaneous capture of passing and trapped fast-ion characteristics.

Main Methods:

• Installation of two high-throughput spectrometer systems on EAST.
• Utilizing Kaiser HoloSpec transmission grating spectrometers and Bunkoukeiki FLP-200 volume phase holographic spectrometers.
• Coupling spectrometers with Princeton Instruments ProEM 1024B eXcelon and Andor DU-888 iXon3 1024 CCD cameras.

Main Results:

• Successful implementation of FIDA systems on EAST, leveraging both co-current and counter-current neutral beam injectors (2-4 MW, 50-80 keV).
• Acquisition of experimental spectra enabling the study of fast-ion behavior.
• Demonstration of simultaneous capture of passing and trapped fast-ion characteristics.

Conclusions:

• The enhanced FIDA systems on EAST provide advanced capabilities for fast-ion research.
• The detailed hardware and spectral data contribute to a deeper understanding of fusion plasma dynamics.
• This advancement supports the development of future magnetic fusion energy devices.