Lithium wall conditioning and surface dust detection on NSTX, and dust removal

C. H. Skinner, Jean Paul Allain, M. G. Bell, F. Q.L. Friesen, B. Heim, M. A. Jaworski, H. Kugel, R. Maingi, B. Rais, C. N. Taylor

Research output: Contribution to journalConference article

Abstract

Lithium evaporation onto National Spherical Torus Experiment (NSTX) plasma-facing components (PFCs) has resulted in improved energy confinement, and reductions in the number and amplitude of edge-localized modes (ELMs) up to the point of complete ELM suppression. The associated PFC surface chemistry has been investigated with a novel plasma-material interface probe connected to an in-vacuo surface analysis station. Analysis has demonstrated that the binding of D atoms to the polycrystalline graphite material of PFCs is fundamentally changed by lithium - in particular, deuterium atoms become weakly bonded near lithium atoms themselves bound to either oxygen or the carbon from the underlying material. Surface dust inside NSTX has been detected in real time using a highly sensitive electrostatic dust detector. In a separate experiment, electrostatic removal of dust via three concentric spiral-shaped electrodes covered by a dielectric and driven by a high-voltage three-phase waveform was evaluated for its potential application to fusion reactors.

Original languageEnglish (US)
Article number014020
JournalPhysica Scripta T
VolumeT145
DOIs
Publication statusPublished - Dec 1 2011
Event13th International Workshop on Plasma-Facing Materials and Components for Fusion Applications, PFMC-13 and 1st International Conference on Fusion Energy Materials Science, FEMaS-1 - Rosenheim, Germany
Duration: May 9 2011May 13 2011

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All Science Journal Classification (ASJC) codes

  • Atomic and Molecular Physics, and Optics
  • Mathematical Physics
  • Condensed Matter Physics

Cite this

Skinner, C. H., Allain, J. P., Bell, M. G., Friesen, F. Q. L., Heim, B., Jaworski, M. A., ... Taylor, C. N. (2011). Lithium wall conditioning and surface dust detection on NSTX, and dust removal. Physica Scripta T, T145, [014020]. https://doi.org/10.1088/0031-8949/2011/T145/014020