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Updated: Jun 7, 2026

10:52
Direct Imaging of Laser-driven Ultrafast Molecular Rotation
Published on: February 4, 2017
A tangentially viewing fast ion D-alpha diagnostic for NSTX
A Bortolon1, W W Heidbrink, M Podestà
1University of California, Irvine, California 92697, USA. abortolo@pppl.gov
The Review of Scientific Instruments
|November 2, 2010
Summary
A new Fast Ion D-alpha (FIDA) diagnostic system will enhance NSTX
Area of Science:
- Plasma physics
- Fusion energy research
- Diagnostic techniques
Background:
- NSTX currently utilizes perpendicular viewing FIDA diagnostics.
- Enhancing diagnostic capabilities is crucial for understanding fast ion behavior in fusion plasmas.
Purpose of the Study:
- To introduce a second Fast Ion D-alpha (FIDA) installation at NSTX.
- To complement existing FIDA diagnostics with tangential viewing.
- To improve velocity-space resolution for detailed fast ion analysis.
Main Methods:
- Installation of two new FIDA instruments with tangential viewing.
- Spectroscopic diagnostic for fast ion spectra and profiles (16 radial points, 5-10 ms resolution).
- Photomultiplier system for FIDA light change measurements (50 kHz sampling rate).
Main Results:
- Minimized spectral contamination due to tangential viewing geometry.
- Enhanced capability to measure fast ion behavior.
- Improved velocity-space resolution for detailed plasma diagnostics.
Conclusions:
- The new FIDA system will provide crucial data on neutral-beam current drive.
- It will offer insights into fast ion acceleration and transport by RF waves and instabilities.
- This advancement supports the understanding of plasma dynamics in fusion devices.
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