Abstract
The response of plasma parameters and broad wavenumber turbulence (1-39 cm-1, kρs = 0.1-10, relevant to ion temperature gradient, trapped electron mode and electron temperature gradient mode turbulence, here ρs = ion gyroradius) to auxiliary electron cyclotron heating (ECH) is reported on. One fluid thermal fluxes and diffusivities increase appreciably with ECH. Significant changes to the density fluctuations over the full range of measured wavenumbers are observed, with an increase for lower wavenumbers and a more spatially complicated response at high k. Spatially resolved high k measurements (k = 39 cm-1, kρs = 4-10) show a varying response to ECH, with decreasing at r/a = 0.35 and increasing at r/a = 0.6 and 1. These variations were found to have a positive correlation with ∇Te evaluated at nearby locations, consistent with a ∇Te drive. Comparison of the changes in high k fluctuation levels with linear gyrokinetic growth rates show qualitative agreement at the innermost location, r/a = 0.35 and disagreement at r/a = 0.6.
Original language | English |
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Pages (from-to) | B183-B193 |
Journal | Plasma Physics and Controlled Fusion |
Volume | 49 |
Issue number | 12 B |
DOIs | |
State | Published - Dec 1 2007 |
Externally published | Yes |