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Title: Electron kinetic effects on interferometry, polarimetry and Thomson scattering measurements in burning plasmas (invited)

At anticipated high electron temperatures in ITER, the effects of electron thermal motion on Thomson scattering (TS), toroidal interferometer/polarimeter (TIP), and poloidal polarimeter (PoPola) diagnostics will be significant and must be accurately treated. The precision of the previous lowest order linear in τ = T{sub e}/m{sub e}c{sup 2} model may be insufficient; we present a more precise model with τ{sup 2}-order corrections to satisfy the high accuracy required for ITER TIP and PoPola diagnostics. The linear model is extended from Maxwellian to a more general class of anisotropic electron distributions that allows us to take into account distortions caused by equilibrium current, ECRH, and RF current drive effects. The classical problem of the degree of polarization of incoherent Thomson scattered radiation is solved analytically exactly without any approximations for the full range of incident polarizations, scattering angles, and electron thermal motion from non-relativistic to ultra-relativistic. The results are discussed in the context of the possible use of the polarization properties of Thomson scattered light as a method of T{sub e} measurement relevant to ITER operational scenarios.
Authors:
; ; ;  [1] ; ;  [2]
  1. Physics Department, University of Wisconsin - Madison and the Center for Magnetic Self-Organization in Laboratory and Astrophysical Plasmas, Madison, Wisconsin 53706 (United States)
  2. Department of Physics and Astronomy, University of California Los Angeles, Los Angeles, California 90095 (United States)
Publication Date:
OSTI Identifier:
22303824
Resource Type:
Journal Article
Resource Relation:
Journal Name: Review of Scientific Instruments; Journal Volume: 85; Journal Issue: 11; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; ACCURACY; ANALYTICAL SOLUTION; ANISOTROPY; CORRECTIONS; ECR HEATING; ELECTRON TEMPERATURE; ELECTRONS; HOT PLASMA; INTERFEROMETRY; ITER TOKAMAK; POLARIMETRY; THOMSON SCATTERING