Impact of the Wall Conditioning Program on Plasma Performance in NSTX
Authors: H.W. Kugel, V. Soukhanovskii, M. Bell, W. Blanchard, D. Gates, B. LeBlanc, R. Maingi, D. Mueller, H.K. Na, S. Paul, C.H. Skinner, D. Stutman, and W.R. Wampler
Date of PPPL Report: July 2002
Presented at: the 15th International Conference on Plasma Surface Interactions in Controlled Fusion Devices, Gifu, Japan, May 27-31, 2002.
High performance operating regimes have been achieved on NSTX through impurity control and wall conditioning techniques. These techniques include HeGDC-aided boronization using deuterated trimethylboron, inter-discharge HeGDC, 350 degrees Celsius PFC bake-out followed by D2 and HeGDC, and experiments to test fueling discharges with either a He-trimethylboron mixture or pure trimethylboron. The impact of this impurity and density control program on recent advances in NSTX plasma performance is discussed.