Evidence for fast-ion transport by microturbulence
W W Heidbrink1, J M Park, M Murakami
1University of California, Irvine, CA 92697, USA.
Physical Review Letters
|November 13, 2009
Abstract:
Cross-field diffusion of energetic ions by microturbulence is measured during neutral-beam injection into the DIII-D tokamak. Fast-ion D(alpha), neutron, and motional Stark effect measurements diagnose the fast-ion distribution function. As expected for transport by plasma turbulence, anomalies relative to the classical prediction are greatest in high temperature plasmas, at low fast-ion energy, and at larger minor radius. Theoretical estimates of fast-ion diffusion are comparable to experimental levels.
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