Stochastic broadening of the scrapeoff layer of a single-null divertor tokamak

摘要

Magnetic perturbations cause the region near the separatrix of a magnetic divertor to become stochastic. The last magnetic surface to provide magnetic confinement passes inside the X-point a distance that is proportional to the square root of the applied perturbation. Particles that diffuse across the last confining surface can follow open magnetic lines to the divertor plates. The strike points of these field lines on the divertor plates lie in helical discrete stripes. The properties of these stripes is important for determining if one can control the heat loads on divertor plates as well as assessing the effects of natural perturbations, such as MHD activity, on divertor designs.