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Updated: Jul 29, 2026

Scanning SQUID Study of Vortex Manipulation by Local Contact
Published on: February 1, 2017
Scale size of magnetic turbulence in tokamaks probed with 30-MeV electrons
Entrop1, Lopes Cardozo NJ, Jaspers
1FOM-Instituut voor Plasmafysica "Rijnhuizen," Association Euratom-FOM, P.O. Box 1207, 3430 BE Nieuwegein, The Netherlands.
Abstract:
Measurements of synchrotron radiation emitted by 30-MeV runaway electrons in the TEXTOR-94 tokamak show that the runaway population decays after switching on neutral beam injection (NBI). The decay starts only with a significant delay, which decreases with increasing NBI heating power. This delay provides direct evidence of the energy dependence of runaway confinement, which is expected if magnetic modes govern the loss of runaways. Application of the theory by Mynick and Strachan [Phys. Fluids 24, 695 (1981)] yields estimates for the "mode width" (delta) of magnetic perturbations: delta<0.5 cm in Ohmic discharges, increasing to delta = 4.4 cm for 0. 6 MW NBI.
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