Global Particle Balances and Wall Recycling Changes During the RMP Induced Density Pump-out in DIII-D H-mode Plasmas

Resonant magnetic perturbations (RMPs) have been shown to successfully suppress ELMs in DIII-D. A drop in electron density up to 30\% during application of the RMP field usually precedes the suppression and/or mitigation of ELMs at high and low edge electron collisionality ($\nu_e^*$). Consequently, an understanding of the density response to the RMP is a critical issue for achieving ELM suppression in ITER. Coincident with this drop in the line-integrated and pedestal densities, the pedestal $T_e$ increases modestly and $T_i$ increases as much as 50\%-70\% depending on the pre-RMP discharge conditions, which contradicts known stochastic transport theory. Global particle balances show that the pump-out magnitude is directly correlated to the particle wall inventory before the RMP. It is observed that the magnitude of the pump-out trends directly with increasing $\beta_N$ and inversely with pedestal collisionality. Recent experimental results where wall conditions were systematically varied will also be presented.