Millimeter-wave imaging diagnostics systems on the EAST tokamak (invited)

Area of Science:

• Plasma physics
• Fusion energy research
• Diagnostic techniques

Background:

• Tokamak devices require advanced diagnostics for plasma behavior studies.
• Electron temperature and density fluctuations are key parameters in fusion plasma research.
• Existing imaging diagnostics have limitations in spatial coverage and simultaneous measurement capabilities.

Purpose of the Study:

• To develop and integrate advanced millimeter-wave imaging diagnostics on the EAST tokamak.
• To enable simultaneous, co-located 2D measurements of electron temperature and density fluctuations.
• To enhance spatial and temporal resolution for plasma instability analysis.

Main Methods:

• Installation of a 384-channel Electron Cyclotron Emission Imaging (ECEI) system (F-band, 90-140 GHz).
• Development and planned installation of a 4th generation Microwave Imaging Reflectometry (MIR) system (W-band, 75-110 GHz).
• Integration of ECEI and MIR systems using a novel 'general optics structure' sharing a common mid-plane port.

Main Results:

• The ECEI system provides high-resolution 2D electron temperature fluctuation images.
• The integrated system allows for simultaneous 2D measurements of both electron temperature and density.
• Innovative front-end optics extend radial and poloidal coverage for both diagnostics.
• Intelligent remote-control systems enable real-time focusing and channel attenuation adjustments.

Conclusions:

• The co-located ECEI and MIR systems represent a significant advancement in tokamak plasma diagnostics.
• These diagnostics offer unprecedented capabilities for studying 2D plasma fluctuations.
• The integrated millimeter-wave imaging approach enhances understanding of plasma dynamics in fusion devices.