Electron Cyclotron Modification of Profiles in Quiescent Double Barrier (QDB) Discharges on DIII-D

High performance QDB conditions form when an internal transport barrier is created with intense neutral-beam injection into quiescent H-mode plasmas. We are exploring a variety of techniques to improve QDB parameters. In experiments using ECH/ECCD we observed a strong dependence on the q-profile when EC-power is used inside the core transport barrier. While strong electron heating is observed, we also observe a drop in the other core parameters; $T_i$, rotation, $n_e$ and impurities. These dynamically changing conditions provide a scan of core temperature profile ratio with $0.3<(T_e/T_i)_{axis}<0.8$ observed. We are exploring the correlation and effects of observed density profile changes with respect to these time-dependent variations in the temperature ratio. Thermal and particle diffusivity calculations indicate a consistency between the rise in temperature ratio and an increase in transport corresponding to the changes in density.