Response of Impurity Particle Confinement Time to External Acuators in QA-mode Plasmas on DIII-D
Authors: B.A. Grierson, et. al.
Abstract:
A series of quiescent H-mode discharges have been executed with the
speci c aim of determining the particle con nement time of impurities in the
presence of the edge harmonic oscillation. These discharges utilize non-intrinsic,
non-recycling fully-stripped flouorine as the diagnostic species monitored by charge-
exchange recombination spectroscopy. It is found that the EHO is an efficient means
of impurity expulsion from the core plasma, with impurity exhaust rates exceeding
those in companion ELMing discharges. As the external torque from neutral beam
injection is lowered, the global energy con nement time increases while the impurity
con nement time does not display an increase.
__________________________________________________
Submitted to: Nuclear Fusion (December 2013)
__________________________________________________
Download PPPL-4980 (pdf 275 KB 15 pp)
__________________________________________________