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Laser system for high resolution Thomson scattering diagnostics on the COMPASS tokamak
1Institute of Plasma Physics AS CR, v.v.i., EURATOM IPP.CR, Za Slovankou 1782/3, 18200 Prague 8, Czech Republic. bohm@ipp.cas.cz
The Review of Scientific Instruments
|November 2, 2010
Summary
A new Thomson scattering diagnostic for the COMPASS tokamak utilizes a dual Nd:YAG laser system. This setup achieves precise 3 mm spatial resolution at the plasma edge, crucial for fusion research.
Area of Science:
- Plasma Physics
- Fusion Energy
- Optical Diagnostics
Background:
- The COMPASS tokamak requires advanced diagnostics for plasma characterization.
- High spatial resolution is essential for studying plasma edge phenomena.
- Existing Thomson scattering systems may have limitations in resolution or flexibility.
Purpose of the Study:
- To design and implement a new Thomson scattering diagnostic for the COMPASS tokamak.
- To achieve approximately 3 mm spatial resolution at the plasma edge.
- To detail the laser source, beam transport, and focusing optics.
Main Methods:
- Utilized a multilaser solution with two 30 Hz, 1.5 J Nd:YAG laser systems.
- Implemented a laser beam transport path from an external location (20 m from tokamak).
- Developed and used a test path of equivalent optical length for performance evaluation.
Main Results:
- The new diagnostic is designed for stringent spatial resolution requirements.
- The multilaser approach with Nd:YAG lasers at 1064 nm is detailed.
- Performance tests on the laser system via the test path were conducted.
Conclusions:
- The designed Thomson scattering diagnostic is being installed on the COMPASS tokamak.
- The chosen laser system and beam path design meet the high-resolution requirements.
- The system's performance was validated through dedicated testing.
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