Heat-flux footprints for I-mode and EDA H-mode plasmas on Alcator C-Mod
Author(s)Terry, James L.; Labombard, Brian; Brunner, Daniel Frederic; Hughes, Jerry W., Jr.; Reinke, Matthew Logan; Whyte, Dennis G.; ... Show more Show less
MetadataShow full item record
IR thermography is used to measure the heat flux footprints on C-Mod’s outer target in I-mode and EDA H-mode plasmas. The footprint profiles are fit to a function with a simple physical interpretation. The fit parameter that is sensitive to the power decay length into the SOL, λ[subscript SOL], is ~1–3× larger in I-modes than in H-modes at similar plasma current, which is the dominant dependence for the H-mode λ[subscript SOL]. In contrast, the fit parameter sensitive to transport into the private-flux-zone along the divertor leg is somewhat smaller in I-mode than in H-mode, but otherwise displays no obvious dependence on I[subscript p], B[subscript t], or stored energy. A third measure of the footprint width, the “integral width”, is not significantly different between H- and I-modes. Also discussed are significant differences in the global power flows of the H-modes with “favorable” ∇B drift direction and those of the I-modes with “unfavorable” ∇B drift direction.
DepartmentMassachusetts Institute of Technology. Department of Nuclear Science and Engineering; Massachusetts Institute of Technology. Plasma Science and Fusion Center
Journal of Nuclear Materials
Terry, J.L., B. LaBombard, D. Brunner, J.W. Hughes, M.L. Reinke, and D.G. Whyte. “Heat-Flux Footprints for I-Mode and EDA H-Mode Plasmas on Alcator C-Mod.” Journal of Nuclear Materials 438 (July 2013): S212–S215.
Author's final manuscript