ISSN:
1089-7674
Source:
AIP Digital Archive
Topics:
Physics
Notes:
Measurements of the steep transport barrier at the edge of the Alcator C-Mod tokamak [I. H. Hutchinson et al., Phys. Plasmas 1, 1511 (1994)] are presented. The parameters at the top of this barrier are in the range Te=150–750 eV and ne=0.5−3.3×1020 m−3, depending on the confinement regime. Type III edge localized modes (ELMs) have an upper temperature limit. Te pedestal profiles show a barrier width ΔT(similar, equals)8 mm. Soft x-ray emissivity profiles are narrower, with Δ=2–4 mm. Edge currents are calculated to alter the ideal stability boundary favorably, leading to ideally stable pedestal profiles. High frequency, broadband, edge density fluctuations are sometimes observed in H-mode (high-confinement mode) and are associated with enhanced particle transport. Coherent magnetic fluctuations localized near the pedestal are also seen. © 1998 American Institute of Physics.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.872843
Permalink