Divertor experiment in the W7-AS stellarator

In view of the near future operation of large stellarators (e.g. LHD and W7-X), the search for adequate power and particle exhaust scenarios comparable to those in tokamak divertors has become mandatory. A promising option consistent with stellarator-specific confinement concepts is to utilize the flux diversion by macroscopic magnetic islands at the plasma boundary in combination with properly arranged targets and baffles for island divertors. Nevertheless, the suitability of this concept has not yet been proven. For this reason, the W7-AS experimental programme will be focused on island divertor studies during the final two years of operation (2000 - 2001). (author)