TITLE

Far-field sheaths due to fast waves incident on material boundaries

AUTHOR(S)
D'Ippolito, D. A.; Myra, J. R.; Jaeger, E. F.; Berry, L. A.
PUB. DATE
October 2008
SOURCE
Physics of Plasmas;Oct2008, Vol. 15 Issue 10, p102501
SOURCE TYPE
Academic Journal
DOC. TYPE
Article
ABSTRACT
The problem of “far-field” sheath formation is studied with a new quantitative one-dimensional model. These radio-frequency (rf) sheaths occur when unabsorbed fast waves in the ion cyclotron range of frequencies are incident on a conducting surface not aligned with a flux surface. Use of a nonlinear sheath boundary condition gives self-consistent solutions for the wave fields and sheath characteristics, and it introduces a sheath-plasma-wave resonance which can enhance the sheath potential. The model is used to compute the parametric dependence of the far-field sheath potential. Its application to post-process the rf fields computed by a full-wave code for a typical D(H) minority heating scenario is also discussed. This work shows that two-dimensional effects (included heuristically) are essential in determining whether far-field sheath potentials are strong enough to cause significant edge interactions, such as impurity generation and reduced heating efficiency.
ACCESSION #
35103363

 

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