Features of radial electric field in impurity-seeded, detached plasma in a tokamak

Abstract

By modeling done with the SOLPS-ITER transport code, it is demonstrated that moderate radiating impurity seeding leads to the increase in the radial electric field by absolute value, while radial electric field remains close to the neoclassical one. In the seeded detached regime with a highly radiating X-point, the radial electric field deviates considerably from the neoclassical electric field. The radial dimension of the zone with increased poloidal com.elsevier.xml.ani.Math@504a4ed rotation shear is larger by absolute value than that corresponding to the moderate seeding. This effect might lead to the shift of the transport barrier further to the core and can partially compensate energy losses rise inside the separatrix, so the pedestal improvement might take place.