Electron transport analysis in TCV

A TCV plasma with high power density (up to 8MW/m%^3$) core deposited ECR heating at significant plasma densities ($\leq7 \times 10^{19}$ m$^{-3}$) is analyzed for the electron thermal transport. The discharge has four distinct high confinement mode (H-mode) phases, an ohmic H-mode with type III edge localized modes (ELMs), a type I ELMy H-mode with the ECRH on, two quasi-stationary ELM-free H-modes, one of which without magneto-hydrodynamics (MHD) and one with. For all four phases both large-scale TEM and ITG modes and small-scale ETG modes are analyzed. For easy comparison of the results, a dimensionless error measure, the so-called average relative variance (ARV) is introduced. According to this method the ETG model explains 70\% of the variation in the electron heat diffusivity whereas the predictive capabilities of the TEM-ITG models are poor. These results for TCV support the conclusion that the ETG model is able to explain a wide range of anomalous electron transport data, in addition to existing evidence from ASDEX, Tore Supra and FTU.