Observations of Thermal Transport Enhancement in Stochastic Boundary Experiments at DIII-D and TEXTOR

Comparison of stochastic boundary experiments in TEXTOR L-modes to DIII-D H-modes shows on both experiments a $q_{95}$ resonance in the pedestal pressure $p_e$ which is driven by a resonant decrease of the pedestal electron temperature $T_e$ as $q_{95}$ is varied. This decrease in $T_e$ is correlated to an increase in the modeled stochastic layer width while the electron density does not show a strong $q_{95}$ resonance. The $T_e$ decrease is only seen for DIII-D in an ITER similar shape at high triangularity as opposed to an increase in $T_e$ and a small effect only on the thermal transport for low triangularity plasmas. This indicates significant shape dependence for the $q_{95}$ resonant thermal transport features in stochastic boundary experiments for suppression of type-I edge localized modes by RMP at DIII-D.