Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2011-5-17
pubmed:abstractText
The present work is motivated by a long standing discrepancy between the electron temperature measurements of Thomson scattering (TS) and electron cyclotron emission (ECE) diagnostics for plasmas with strong auxiliary heating observed at both JET and TFTR above 6–7 keV, where in some cases the ECE electron temperature measurements can be 15%–20% higher than the TS measurements. Recent analysis based on ECE results at JET has shown evidence of distortions to the Maxwellian electron velocity distribution and a correlation with the TS and ECE discrepancies has been suggested. In this paper, a technique to determine the presence of non-Maxwellian behavior using TS diagnostics is outlined. The difficulties and limitations of modern TS system designs to determine the electron velocity distribution are also discussed. It is demonstrated that small deviations such as those suggested by previous ECE analysis could be potentially detected, depending on the spectral layout of the TS polychromators. The spectral layout of the JET high resolution Thomson scattering system is such that it could be used to determine these deviations between 1 and 6 keV, and the results presented here indicate that no evidence of non-Maxwellian behavior is observed in this range. In this paper, a modification to the current polychromator design is proposed, allowing non-Maxwellian distortions to be detected up to at least 10 keV.
pubmed:language
eng
pubmed:journal
pubmed:status
PubMed-not-MEDLINE
pubmed:month
Mar
pubmed:issn
1089-7623
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
82
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
033514
pubmed:year
2011
pubmed:articleTitle
Detecting non-maxwellian electron velocity distributions at JET by high resolution Thomson scattering.
pubmed:affiliation
Department of Electrical and Electronic Engineering, University College Cork, Association Euratom-DCU, Cork, Ireland. kieranb@eleceng.ucc.ie
pubmed:publicationType
Journal Article