Resonant magnetic perturbation (RMP) induced ELM suppression in the DIII-D SAS-VW tungsten slot divertor

Suppression of edge-localized modes (ELMs) was achieved for the first time in the DIII-D tungsten-coated slot divertor (SAS-VW). Robust ELM suppression was sustained for periods >1500 ms with application RMPs of toroidal mode number n=3 at an edge safety factor, q₉₅, of 3.7-3.8 and an edge pedestal electron collisionality, ν*, of ~0.15. A gradual build-up of spectroscopically measured W core content, attributed partially to an increased W source from the divertor, occurred throughout this period. Intermittent periods of ELM suppression (100-150 ms) were also observed during application of n=2 RMPs at a q₉₅ value of 4.0. Increased divertor electron temperatures during the ELM-suppressed phase likely causes the additional W sputtering, but 0.5-1 MW of electron cyclotron heating was applied near the magnetic axis (ρ~0.2-0.3) to inhibit W accumulation. Measurements of W levels deposited on collector probes in the far scrape-off-layer will also be presented. Demonstration of a scenario without damaging edge transients and power exhausted into a slot-like, tungsten divertor represents notable progress towards an integrated core-edge solution for future devices.