Twelve channel ECE diagnostic system of the new wendelstein stellarator W VII-AS

WENDELSTEIN VII-AS is a modular stellarator with 5 toroidal field periods, an aspect ratio of 10 and a large radius of 2 m. It is an upgrade version of the 1985 shut down W VII-A using twisted coils instead of main field coils and helical windings forming an optimized magnetic configuration. Main design guidelines for the advanced stellarator concept have been the minimization of parallel currents and of deviations of particles from the magnetic surfaces which leads to higher plasma equilibrium pressure and a reduction of transport losses. The experiment is scheduled to become operational in late 1987.