Impurities removal during central ECR heating in T10

Impurities removal during central ECR heating in T-10 L. A. Klyuchnikov 1, V. A. Krupin 1, K. V. Korobov 1, A. R. Nemets 1, M. R. Nurgaliev, A. Yu. Dnestrovskij 1, D. S. Denschikov 1, A. A. Borschegovskij 1, N. N. Naumenko 2, D. V. Sarychev 1, D. S. Sergeev 1, A. V. Sushkov 1, G. N. Tilinin 1, S. N. Tugarinov 1 FIG. 12. Modeling of carbon and oxygen concentrations in discharge with Ip=180 k. A in OH plasma (left column) and in ECRH regime with PECRH=1 MW (right column). A high efficiency of impurities removal from plasma center using ECRH was demonstrated in discharges with initial neoclassical peaking of impurities. Effect of ECRH leads to decrease concentrations of light impurities in plasma center up to three times at low plasma currents and high electron densities. There is an obvious connection between efficiency of impurities removal and the gradient of impurities concentration, which indicates the domination of diffusive processes in impurities removal with ECRH. In conditions of sufficient change of transport coefficient from neoclassical values to a strong anomalous coefficients in ECRH stage, there is a possibility of using of dynamics of light impurities (measured by CXRS) and heavy impurities (evaluated from AXUV and SXR) for the determination of impurities anomalous transport coefficients in ECRH stage. A modeling of dynamics of removal of light impurities was provided. The characteristic value of additional anomalous diffusion, initiated by ECRH, is ~1. 5 m 2/s.