First Experimental Results of Tungsten Transport Investigations in the T-10 Tokamak Plasma

Abstract

The investigations of tungsten transport in T-10 plasma are presented in the current paper. The process of tungsten accumulation in OH discharges and its dependence on parameters n_e, I_p, and Zeff are discussed. Peaked tungsten density profiles n_W(r) are observed in plasmas with Z_eff ≈ 1–1.5. In plasmas with Z_eff ≈ 3–4, W accumulation is mainly integral with no profile peaking with regard to electron density n_e(r). Lower densities of W are observed in discharges with a lithized T-10 vacuum vessel in comparison with plasma contaminated with light impurities. The disposal of W accumulation is produced by auxiliary ECRH input. During the central ECRH, the tungsten density profile flattens with the central density drop off by ~10 times together with W source increase up to 4 times.