readme.txt

Title of paper	Advances in boronization on NSTX-Upgrade

Author(s)	C. H Skinner, F. Bedoya, F. Scotti, J.P. Allain, W. Blanchard, D. Cai, M. Jaworski, B.E. Koel.

Name of Journal 	Nuclear Materials and Energy

Abstract: Boronization has been effective in reducing plasma impurities and enabling access to higher density, higher confinement plasmas in many magnetic fusion devices. The National Spherical Torus eXperiment, NSTX, has recently undergone a major upgrade to NSTX-U in order to develop the physics basis for a ST-based Fusion Nuclear Science Facility (FNSF) with capability for double the toroidal field, plasma current, and NBI heating power and increased pulse duration from 1Ð1.5 s to 5Ð8 s. A new deuterated tri-methyl boron conditioning system was implemented together with a novel surface analysis diagnostic. We report on the spatial distribution of the boron deposition versus discharge pressure, gas injection and electrode location. The oxygen concentration of the plasma facing surface was measured by in-vacuo XPS and increased both with plasma exposure and with exposure to trace residual gases. This increase correlated with the rise of oxygen emission from the plasma.

Attached data files are 
Fig 1 pdf drawing file
Fig 2 jpg image
Figs 3 - 7 cdv files containing X,Y coordinates of points in plots.