Particle flux and radial profiles in the SOL of DIII-D during ELMing H-mode

Abstract The radial particle flux in the scrape-off-layer (SOL) during ELMing H-mode is examined in DIII-D as a function of density. The global radial particle flux in the outboard far SOL is determined by a window frame technique. Between ELMs, the outboard far SOL particle flux increases strongly with density and remains similar to the particle flux across the separatrix as estimated by the pedestal density and temperature gradients. At low density the steep density gradient of the pedestal extends up to 2 cm outside the separatrix, while at high density the density gradient flattens just outside the separatrix. During ELMs the far SOL particle flux becomes localized to the outboard midplane and the assumptions for the window frame analysis break down. Implications for scaling of outboard main chamber wall particle flux and pedestal fueling are explored.