Abstract
Transport of iron in TFTR discharges heated by 6.7 MW of co-injected neutral beam power has been studied by spatially resolved charge exchange recombination spectroscopy in the visible region of the spectrum. Thç time evolutions of the densities of Fe24+ and Fe23+ ions following injection of iron are modelled by the neoclassical flux plus a moderately hollow diffii- sivity, increasing linearly from 1.3 m2/s on axis to 2.4 m2/s at the plasma edge. For r/a > 0.5, the iron diffusivity is significantly smaller than the helium diffusivity measured in identical discharges, while it is larger in the region immediately surrounding the plasma axis.
Original language | English |
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Pages (from-to) | 171-175 |
Number of pages | 5 |
Journal | Nuclear Fusion |
Volume | 31 |
Issue number | 1 |
DOIs | |
State | Published - Jan 1991 |