Plasma potential evolution in various operational modes in the TUMAN-3M tokamak
2007 (English)In: 34th EPS Conference on Plasma Physics 2007, EPS 2007 - Europhysics Conference Abstracts, 2007, no 3, 2010-2013 p.Conference paper (Refereed)
In a scenario with Counter-NBI it was found using HIBP that, due to the NBI effect (most probably, orbit loss with some heating and momentum impact), core plasma potential plasma gradually became more negative (for ∼200V). Strong positive perturbation of the core plasma potential was registered by the HIBP during the burst of peripheral MHDs with low m, n. If such a burst takes place in the H-mode (both ohmic and counter-NBI heated), the positive potential perturbation leads to H-mode termination. The most probable mechanism of the positive field build-up during MHD burst is though to be a loss of fast electrons along partly disturbed magnetic field lines near the island's separatrix [3,4]. This mechanism is similar to the ergodic divertor's action on the TEXTOR , where radial electric field modification by the electron loses was also discussed. A quantitative analysis of the subject may be found in . Similar mechanism may be responsible for a positive perturbation of central plasma potential registered in the sawtooth crashes. The GAM with δφ/φ∼0.3 and δφ/φ≫δn/n∼0.05 where observed with HIBP in a core region of the TUMAN-3M r/a∼0.33 in the current ramp phase. Further studies are needed to reveal a possible connection between the GAM evolution and plasma confinement in the TUMAN-3M.
Place, publisher, year, edition, pages
2007. no 3, 2010-2013 p.
Magnetoplasma, Plasma confinement, Plasma simulation, Tokamak devices
IdentifiersURN: urn:nbn:se:kth:diva-154682ScopusID: 2-s2.0-84873831696ISBN: 978-162276334-4OAI: oai:DiVA.org:kth-154682DiVA: diva2:758453
34th European Physical Society Conference on Plasma Physics 2007, EPS 2007, 2 July 2007 through 6 July 2007, Warsaw, Poland
QC 201410272014-10-272014-10-272014-10-27Bibliographically approved