Magnetic field line diversion in Helias stellarator configurations: perspectives for divertor operation

The vacuum magnetic field outside the last closed magnetic surface of Helias stellarator configurations is investigated with respect to its field line diversion properties. Especially, a divertor concept is presented which makes use of the diversion properties and does not depend on the special island structure outside the plasma boundary. To obtain a more realistic description of the diversion process, the effect of particle diffusion perpendicular to the magnetic field lines is simulated in a simplified scrape-off layer model