Stellarator Edge and Divertor Physics
The experimental division "Stellarator Edge and Divertor Physics" (E4) investigates – in close collaboration with the divisions for Stellarator Dynamics and Transport, Stellarator Heating and Optimization and Stellarator Theory – the capability of the stellarator concept for a fusion power plant. Numerous instruments for plasma properties in the Wendelstein 7-X stellarator are operated in this division.
The research in the division focuses on the important edge region of the plasma of the Wendelstein 7-X stellarator. This region separates the hot plasma core from the cooler vessel wall. The plasma particles flowing out of the confined region are guided by magnetic field lines to target plates in the so-called divertor. The special magnetic topology at the edge of W7-X is called an island chain, and the entire concept is referred to as an island divertor configuration. The stellarator island divertor concept may have important advantages over the standard tokamak divertor concept. Another important research area in the division is that of plasma-wall interactions.
The division E4 is also responsible for the construction and operation of a number of instruments that allow to diagnose various properties of the W7-X plasma.
Projects within E4:
- Flux-Surface Measurements (see Highlights)
- Divertor Thermography /Hα
- Langmuir Probes (see diagnostics)
- Pellet injection
- Neutral Gas Pressure Gauges
- Penning gauges
- Visible Spectroscopy
- Bremsstrahlung Zeff
- Thermal Helium-Beam
- Video Diagnostics
- Test Divertor Unit - Scraper Element
Many of these diagnostics are described in a recent publication in Journal of Instrumentation.