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arXiv · 1508.00424

Charge dependence of neoclassical and turbulent transport of light impurities on MAST

S. S. Henderson·L. Garzotti·F. J. Casson·D. Dickinson·M. O'Mullane·A. Patel·C. M. Roach·H. P. Summers·H. Tanabe·M. Valovic·the MAST team
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Abstract

Carbon and nitrogen impurity transport coefficients are determined from gas puff experiments carried out during repeat L-mode discharges on the Mega-Amp Spherical Tokamak (MAST) and compared against a previous analysis of helium impurity transport on MAST. The impurity density profiles are measured on the low-field side of the plasma, therefore this paper focuses on light impurities where the impact of poloidal asymmetries on impurity transport is predicted to be negligible. A weak screening of carbon and nitrogen is found in the plasma core, whereas the helium density profile is peaked over the entire plasma radius.

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S. S. Henderson, L. Garzotti, F. J. Casson, D. Dickinson, M. O'Mullane, A. Patel, C. M. Roach, H. P. Summers, H. Tanabe, M. Valovic, the MAST team. 2015-08-03. Charge dependence of neoclassical and turbulent transport of light impurities on MAST. https://doi.org/10.1088/0741-3335/57/9/095001

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