Dual Langmuir-probe array for 3D plasma studies in TORPEX

Area of Science:

• Plasma physics
• Fusion energy research
• Diagnostic techniques

Background:

• Understanding plasma behavior is crucial for fusion energy.
• TORPEX requires advanced diagnostics for 3D plasma characterization.
• Existing methods may lack comprehensive 3D spatial resolution.

Purpose of the Study:

• To design and implement a novel Langmuir probe (LP) array diagnostic system.
• To enable the determination of basic three-dimensional (3D) plasma features in TORPEX.
• To provide comprehensive poloidal cross-section coverage at distinct toroidal locations.

Main Methods:

• Installation of two identical LP arrays at opposing sides of the TORPEX apparatus.
• Utilizing cross-correlation studies of signals from the LP arrays for 3D information extraction.
• Employing advanced front-end electronics for high signal-to-noise ratio.
• Reconstructing 3D plasma structures by combining data from all probes.
• Tracking evolving plasma structures through data analysis.
• Incorporating a radial linear-motion mechanism for probe positioning adjustments.

Main Results:

• Successful design and installation of the LP array diagnostic.
• Demonstrated capability to extract basic 3D plasma information through cross-correlation.
• Achieved reconstruction of elementary 3D plasma structures at each time step.
• Enabled tracking of plasma structure evolution over time.
• High signal-to-noise performance of the front-end electronics confirmed.

Conclusions:

• The new LP array diagnostic effectively provides 3D plasma insights in TORPEX.
• The diagnostic facilitates the study of plasma dynamics and structure evolution.
• This advancement enhances the diagnostic capabilities for fusion research in TORPEX.