Dynamic simulation of redeposition of backscattered and sputtered particles on tungsten irradiated by plasmas

Redeposition of backscattered and sputtered particles due to their ionization and gyromotion in the scrape-off layer (SOL) is investigated using a dynamic simulation model of interaction of Maxwellian carbon ions with a tungsten surface. The implantation of projectile carbon ions during their bombardment causes reduction in the amounts of sputtered tungsten and backscattered carbon ions, and it causes an additional sputtering of carbon. Due to redeposition of emitted particles on the surface, the sputtering of tungsten (implanted carbon) is more (less) suppressed. Furthermore, a thick carbon layer is deposited on the tungsten surface at high SOL plasma temperatures, at which the surface is eroded if no redeposition is included in the simulation. (author)