Effect of Boronization on Ohmic Plasmas in NSTX.

Skinner, C. H. ; Kugel, H. ; Maingi, R. ; Wampler, W. R. ; Blanchard, W. ; Bell, M. ; Bell, R. ; LeBlanc, B. ; Gates, D. ; Kaye, S. ; LaMarche, P. ; Menard, J. ; Mueller, D. ; Na, H. K. ; Nishino, N. ; Paul, S. ; Sabbagh, S. ; Soukhanovskii, V.

Technical Information Center Oak Ridge Tennessee

关键词: Plasma;    NSTX device;    Boron;    First wall;    Carbon;   

RP-ID  :  DE2001781481

学科分类：工程和技术（综合）

美国|英语

来源: National Technical Reports Library

【 摘 要 】

Boronization of the National Spherical Torus Experiment (NSTX) has enabled access to higher density, higher confinement plasmas. A glow discharge with 4 mTorr helium and 10% deuterated trimethyl boron deposited 1.7 g of boron on the plasma facing surfaces. Ion beam analysis of witness coupons showed a B+C areal density of 10 to the 18 (B+C) cm to the -2 corresponding to a film thickness of 100 nm. Subsequent ohmic discharges showed oxygen emission lines reduced by x15, carbon emission reduced by two and copper reduced to undetectable levels. After boronization, the plasma current flattop time increased by 70% enabling access to higher density, higher confinement plasmas.