skip to main content

Title: Probing the plasma near high power wave launchers in fusion devices for static and dynamic electric fields (invited)

An exploratory study was carried out in the long-pulse tokamak Tore Supra, to determine if electric fields in the plasma around high-power, RF wave launchers could be measured with non-intrusive, passive, optical emission spectroscopy. The focus was in particular on the use of the external electric field Stark effect. The feasibility was found to be strongly dependent on the spatial extent of the electric fields and overlap between regions of strong (>∼1 kV/cm) electric fields and regions of plasma particle recycling and plasma-induced, spectral line emission. Most amenable to the measurement was the RF electric field in edge plasma, in front of a lower hybrid heating and current drive launcher. Electric field strengths and direction, derived from fitting the acquired spectra to a model including time-dependent Stark effect and the tokamak-range magnetic field Zeeman-effect, were found to be in good agreement with full-wave modeling of the observed launcher.
Authors:
; ; ; ; ; ;  [1] ;  [1] ;  [2] ; ; ; ; ; ; ; ; ; ;  [3] ;  [4]
  1. Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831-6169 (United States)
  2. (United States)
  3. CEA, IRFM, F-13108 Saint Paul-lez-Durance (France)
  4. North Carolina State University, Raleigh, North Carolina 27607 (United States)
Publication Date:
OSTI Identifier:
22308639
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; EDGE LOCALIZED MODES; ELECTRIC FIELDS; EMISSION SPECTROSCOPY; LOWER HYBRID HEATING; MAGNETIC FIELDS; PLASMA; PROBES; SIMULATION; STARK EFFECT; THERMONUCLEAR REACTORS; TIME DEPENDENCE; TORE SUPRA TOKAMAK; ZEEMAN EFFECT