Profile measurements of the electron temperature on the ASDEX Upgrade, COMPASS, and ISTTOK tokamak using Thomson scattering, triple, and ball-pen probes

Journal Article · Fri Apr 15 00:00:00 EDT 2016 · Review of Scientific Instruments

DOI:https://doi.org/10.1063/1.4945797· OSTI ID:22597131

Horacek, J.; Bilkova, P.; Böhm, P.; Aftanas, M.; Vondracek, P.; Stöckel, J.; Panek, R. ^[1]; Müller, H. W. ^[2]; Silva, C.; Fernandes, H.; Figueiredo, H. ^[3]; Schrittwieser, R.; Ionita, C.; Mehlmann, F.; Costea, S. ^[4]; Kurzan, B. ^[2]

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1. Institute of Plasma Physics, Prague (Czech Republic)
2. Max-Planck-Institute for Plasma Physics, Garching near Munich (Germany)
3. Instituto de Plasmas e Fusão Nuclear, Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisboa (Portugal)
4. Institute for Ion Physics and Applied Physics, University of Innsbruck, Innsbruck (Austria)

The ball-pen probe (BPP) technique is used successfully to make profile measurements of the electron temperature on the ASDEX Upgrade (Axially Symmetric Divertor Experiment), COMPASS (COMPact ASSembly), and ISTTOK (Instituto Superior Tecnico TOKamak) tokamak. The electron temperature is provided by a combination of the BPP potential (Φ{sub BPP}) and the floating potential (V{sub fl}) of the Langmuir probe (LP), which is compared with the Thomson scattering diagnostic on ASDEX Upgrade and COMPASS. Excellent agreement between the two diagnostics is obtained for circular and diverted plasmas and different heating mechanisms (Ohmic, NBI, ECRH) in deuterium discharges with the same formula T{sub e} = (Φ{sub BPP} − V{sub fl})/2.2. The comparative measurements of the electron temperature using BPP/LP and triple probe (TP) techniques on the ISTTOK tokamak show good agreement of averaged values only inside the separatrix. It was also found that the TP provides the electron temperature with significantly higher standard deviation than BPP/LP. However, the resulting values of both techniques are well in the phase with the maximum of cross-correlation function being 0.8.

• OSTI ID: 22597131
• Journal Information: Review of Scientific Instruments, Vol. 87, Issue 4; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA); ISSN 0034-6748
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY
ASDEX TOKAMAK
AXIAL SYMMETRY
COMPARATIVE EVALUATIONS
COMPASS DETECTOR
COMPASS-D TOKAMAK
DEUTERIUM
DIVERTORS
ECR HEATING
ELECTRON TEMPERATURE
ELECTRONS
ISTTOK TOKAMAK
LANGMUIR PROBE
PLASMA
THOMSON SCATTERING