Evidence for fast-ion transport by microturbulence.
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.
Heidbrink
W W
WW
University of California, Irvine, CA 92697, USA.
Park
J M
JM
Murakami
M
M
Petty
C C
CC
Holcomb
C
C
Van Zeeland
M A
MA