Effect of turbulence on impurity transport in the edge and SOL region

Numerical simulations of the interchange plasma turbulence in the presence of medium-Z impurities (N₂, Ne, Ar) seeding have been done. These simulation results are used to study the impurity transport mechanism in the edge and SOL regions. In the edge region, the inward transport of the ionization species (N⁺, Ne⁺, Ar⁺, Ar²⁺) is mainly related to the plasma holes. The cross-correlation between plasma holes and the first ionization species dominates in the edge region, whereas no such cross-correlation exists between the plasma blobs and the first ionization species in this region. The cross-correlation related to the Ar impurity seeding is higher than that of Ne and N₂ seeding. It drops for the higher ionization species. In the SOL region, the transport of these first ionization species is related to the plasma blobs in the outward direction as the cross-correlation between the first ionization species and plasma blobs is high, but no such relation has been found with the density holes. The simulation results validate the theoretical relationship obtained from the blob fraction and blob formation criterion, where the blob fraction is mainly proportional to the radial gradient of the radial electric field. The same tendency has been found for the density holes. Modification of the blob fraction by the impurities has been studied.