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A real-time velocity diagnostic for NSTX
The Review of Scientific Instruments
|April 3, 2012
Summary
A new diagnostic system on the National Spherical Torus Experiment (NSTX) enables rapid plasma toroidal velocity measurements. This system integrates with the NSTX plasma control system for real-time feedback, enhancing plasma control capabilities.
Area of Science:
- Plasma physics
- Fusion energy research
- Diagnostic instrumentation
Background:
- Accurate measurement of plasma toroidal velocity is crucial for understanding and controlling fusion plasmas.
- Existing diagnostics may lack the speed or spatial resolution required for real-time feedback control.
- The National Spherical Torus Experiment (NSTX) requires advanced diagnostics for its operational goals.
Purpose of the Study:
- To introduce a novel diagnostic system for fast measurements of plasma toroidal velocity on NSTX.
- To detail the design, implementation, and initial testing of this advanced diagnostic.
- To demonstrate the system's capability for real-time feedback control of plasma velocity.
Main Methods:
- Installation of an active charge-exchange recombination spectroscopy diagnostic on NSTX.
- Capability for measurements at up to six radial locations.
- High sampling rate of 5 kHz for rapid data acquisition.
- Real-time interface with the NSTX plasma control system.
Main Results:
- Successful installation and initial testing of the plasma toroidal velocity diagnostic.
- Demonstration of high-speed (5 kHz) measurement capability.
- Integration with the plasma control system for potential real-time feedback.
Conclusions:
- The new diagnostic system provides fast and spatially resolved measurements of plasma toroidal velocity on NSTX.
- The system's real-time feedback capability holds significant promise for advanced plasma control in fusion devices.
- Initial tests, including neon glows, validate the diagnostic's performance and readiness for further experiments.
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