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Atomic Spectroscopy on Fusion Relevant Ions and Studies of Light Impurities in the JET Tokamak

Tunklev, Magnus LU (1999)
Abstract (Swedish)
Popular Abstract in Swedish

Kontroll av fororeningar i dagens fusionsmaskiner aer ett inte alltfor stort problem. De kan dock anvandas for diagnostiskt syfte eftersom deras linjeemission avslojar ett flertal intressanta plasmaparametrar. For att kunna maeta egenskaper som jontemperatur, jondensitet och plasmarotation i ett fusionsplasma, aer det av yttersta vikt att den spektroskopiska tolkningen av signalerna ar korrekt. Ett flertal signaler som "skuggar" de signaler vi vill utfora maetningarna pa har undersokts. Detta har lett bla. till battre vaerde pa vaeteatomernas densitet i plasmat. Studier har aven utforts rorande joners transport, detta eftersom plasmats stabillitet och effektivitet aer beroende av de ingaende... (More)
Popular Abstract in Swedish

Kontroll av fororeningar i dagens fusionsmaskiner aer ett inte alltfor stort problem. De kan dock anvandas for diagnostiskt syfte eftersom deras linjeemission avslojar ett flertal intressanta plasmaparametrar. For att kunna maeta egenskaper som jontemperatur, jondensitet och plasmarotation i ett fusionsplasma, aer det av yttersta vikt att den spektroskopiska tolkningen av signalerna ar korrekt. Ett flertal signaler som "skuggar" de signaler vi vill utfora maetningarna pa har undersokts. Detta har lett bla. till battre vaerde pa vaeteatomernas densitet i plasmat. Studier har aven utforts rorande joners transport, detta eftersom plasmats stabillitet och effektivitet aer beroende av de ingaende partiklarnas transportegenskaper. (Less)
Abstract
The spectrum and energy levels C IV and the 3l4l' system of the Mg-like ions in the iron group elements has been investigated. This has led to several hundred identified transitions, many of them previously unknown. Using the Charge Exchange diagnostic system at JET, ion temperatures, rotation velocities and densities have been derived from visible spectroscopic measurements on fully ionised light impurities such as He, C, N and Ne. The existence of plume contribution from beam produced hydrogen-like ions has been proven beyond any doubt to affect the deduction of the active charge exchange signal of He II. In the case of C VI, the plume signal was estimated to be at least a factor of five lower than the active charge exchange signal. Line... (More)
The spectrum and energy levels C IV and the 3l4l' system of the Mg-like ions in the iron group elements has been investigated. This has led to several hundred identified transitions, many of them previously unknown. Using the Charge Exchange diagnostic system at JET, ion temperatures, rotation velocities and densities have been derived from visible spectroscopic measurements on fully ionised light impurities such as He, C, N and Ne. The existence of plume contribution from beam produced hydrogen-like ions has been proven beyond any doubt to affect the deduction of the active charge exchange signal of He II. In the case of C VI, the plume signal was estimated to be at least a factor of five lower than the active charge exchange signal. Line integrated passive charge exchange emission between neutral background atoms and fully ionised impurities has been investigated and modelled. When the synthetic spectrum is fitted to the experimentally detected spectra the neutral background density can be deduced. The importance of including background atoms (H,D and T) as charge exchange donors, not only in state 2s, but also in state 1s, has been shown to be crucial in high temperature shots. Transport of light impurities has been studied with gas puff injections into steady state H-mode plasmas. The results suggest that light impurities are transported as desribed by the neo-classical Pfirsch-Schlueter regime at the edge, whilst in the centre, sawtoothing, preferably to Banana transport, is is mixing the plasma and increases the measured values on the diffusion. For the peaking of impurities in a steady state plasma an anomalous treatment was more in agreement with the experimental data. Certain confinement informations, previously predicted theoretically as a part of the peaking equation, has been experimentally verified. (Less)
Please use this url to cite or link to this publication:
author
opponent
  • Ralph C Isler, Ralph C Isler, General Atomics, P.O. Box 85608, MS 13/353, San Diego, CA 92186-5608
organization
publishing date
type
Thesis
publication status
published
subject
keywords
Active and Passive Charge Exchange, Transport, Diffusion, Convection, Neutral Background Densities, Ion temperatures, Fusion, Isoelectronic sequences, Plasma, Atom- och molekylärfysik, Fysicumarkivet A:1999:Tunklev, Ritz formalism, Plume, Atomic and molecular physics
pages
115 pages
publisher
Magnus Tunklev, Atomic Spectroscopy, Sölveg. 14, 223 62 Lund,
defense location
Lecture hall B, Physics Dep.
defense date
1999-03-05 10:15
external identifiers
  • other:ISRN: LUNFD6/(NFFA-1026)/1-115/(1999)
ISBN
91-7874-048-7
language
English
LU publication?
yes
id
5cdc294c-6396-46a3-98f8-63dbe3968e8e (old id 19085)
date added to LUP
2007-05-24 14:42:23
date last changed
2016-09-19 08:45:05
@phdthesis{5cdc294c-6396-46a3-98f8-63dbe3968e8e,
  abstract     = {The spectrum and energy levels C IV and the 3l4l' system of the Mg-like ions in the iron group elements has been investigated. This has led to several hundred identified transitions, many of them previously unknown. Using the Charge Exchange diagnostic system at JET, ion temperatures, rotation velocities and densities have been derived from visible spectroscopic measurements on fully ionised light impurities such as He, C, N and Ne. The existence of plume contribution from beam produced hydrogen-like ions has been proven beyond any doubt to affect the deduction of the active charge exchange signal of He II. In the case of C VI, the plume signal was estimated to be at least a factor of five lower than the active charge exchange signal. Line integrated passive charge exchange emission between neutral background atoms and fully ionised impurities has been investigated and modelled. When the synthetic spectrum is fitted to the experimentally detected spectra the neutral background density can be deduced. The importance of including background atoms (H,D and T) as charge exchange donors, not only in state 2s, but also in state 1s, has been shown to be crucial in high temperature shots. Transport of light impurities has been studied with gas puff injections into steady state H-mode plasmas. The results suggest that light impurities are transported as desribed by the neo-classical Pfirsch-Schlueter regime at the edge, whilst in the centre, sawtoothing, preferably to Banana transport, is is mixing the plasma and increases the measured values on the diffusion. For the peaking of impurities in a steady state plasma an anomalous treatment was more in agreement with the experimental data. Certain confinement informations, previously predicted theoretically as a part of the peaking equation, has been experimentally verified.},
  author       = {Tunklev, Magnus},
  isbn         = {91-7874-048-7},
  keyword      = {Active and Passive Charge Exchange,Transport,Diffusion,Convection,Neutral Background Densities,Ion temperatures,Fusion,Isoelectronic sequences,Plasma,Atom- och molekylärfysik,Fysicumarkivet A:1999:Tunklev,Ritz formalism,Plume,Atomic and molecular physics},
  language     = {eng},
  pages        = {115},
  publisher    = {Magnus Tunklev, Atomic Spectroscopy, Sölveg. 14, 223 62 Lund,},
  school       = {Lund University},
  title        = {Atomic Spectroscopy on Fusion Relevant Ions and Studies of Light Impurities in the JET Tokamak},
  year         = {1999},
}