title: Profile measurements of the electron temperature on the ASDEX Upgrade, COMPASS, and ISTTOK tokamak using Thomson scattering, triple, and ball-pen probes.
abstract: 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 (ΦBPP) and the floating potential (Vfl) 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 Te = (ΦBPP - Vfl)/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.
authors.affiliation: Institute of Plasma Physics, Prague, Czech Republic.
authors.forename: J
authors.initials: J
authors.lastname: Adamek
authors.affiliation: Max-Planck-Institute for Plasma Physics, Garching near Munich, Germany.
authors.forename: H W
authors.initials: HW
authors.lastname: Müller
authors.affiliation: Instituto de Plasmas e Fusão Nuclear, Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisboa, Portugal.
authors.forename: C
authors.initials: C
authors.lastname: Silva
authors.affiliation: Institute for Ion Physics and Applied Physics, University of Innsbruck, Innsbruck, Austria.
authors.forename: R
authors.initials: R
authors.lastname: Schrittwieser
authors.affiliation: Institute for Ion Physics and Applied Physics, University of Innsbruck, Innsbruck, Austria.
authors.forename: C
authors.initials: C
authors.lastname: Ionita
authors.affiliation: Institute for Ion Physics and Applied Physics, University of Innsbruck, Innsbruck, Austria.
authors.forename: F
authors.initials: F
authors.lastname: Mehlmann
authors.affiliation: Institute for Ion Physics and Applied Physics, University of Innsbruck, Innsbruck, Austria.
authors.forename: S
authors.initials: S
authors.lastname: Costea
authors.affiliation: Institute of Plasma Physics, Prague, Czech Republic.
authors.forename: J
authors.initials: J
authors.lastname: Horacek
authors.affiliation: Max-Planck-Institute for Plasma Physics, Garching near Munich, Germany.
authors.forename: B
authors.initials: B
authors.lastname: Kurzan
authors.affiliation: Institute of Plasma Physics, Prague, Czech Republic.
authors.forename: P
authors.initials: P
authors.lastname: Bilkova
authors.affiliation: Institute of Plasma Physics, Prague, Czech Republic.
authors.forename: P
authors.initials: P
authors.lastname: Böhm
authors.affiliation: Institute of Plasma Physics, Prague, Czech Republic.
authors.forename: M
authors.initials: M
authors.lastname: Aftanas
authors.affiliation: Institute of Plasma Physics, Prague, Czech Republic.
authors.forename: P
authors.initials: P
authors.lastname: Vondracek
authors.affiliation: Institute of Plasma Physics, Prague, Czech Republic.
authors.forename: J
authors.initials: J
authors.lastname: Stöckel
authors.affiliation: Institute of Plasma Physics, Prague, Czech Republic.
authors.forename: R
authors.initials: R
authors.lastname: Panek
authors.affiliation: Instituto de Plasmas e Fusão Nuclear, Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisboa, Portugal.
authors.forename: H
authors.initials: H
authors.lastname: Fernandes
authors.affiliation: Instituto de Plasmas e Fusão Nuclear, Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisboa, Portugal.
authors.forename: H
authors.initials: H
authors.lastname: Figueiredo