Study of the impact of resonant magnetic perturbation fields on gross tungsten erosion using DiMES samples in DIII-D

• Published in: Physica scripta 2017-12, Vol.T170 (1), p.14048
• Main Authors: Hinson, E T, Schmitz, O, Frerichs, H, Abrams, T, Briesemeister, A, Rudakov, D L, Unterberg, E A, Wampler, W R, Watkins, J G, Wang, H Q
• Format: Article
• Language: English
• Subjects: 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; ITER; plasma material interactions; resonant magnetic perturbations; tungsten erosion
• ISSN: 0031-8949; 1402-4896
• DOI: 10.1088/1402-4896/aa9002

An experiment was conducted in DIII-D to compare gross tungsten (W) erosion on samples exposed to outer strike point (OSP) sweeps in L-mode plasmas for three conditions. These included two phases of resonant magnetic perturbations (RMPs), and a set with no perturbations. Upon RMP application, lobe structures indicative of strike point splitting of the OSP were evident in divertor camera data and on Langmuir probes. Gross W erosion flux, Γ W , inferred spectroscopically using the S/XB method applied to the 400.9 nm W-I line, was generally in the range Γ W Γ D + , = 2 × 10 − 4 referenced to incident deuterium ion flux Γ D + , , and was increased in the RMP cases by no more than 30% of the level observed in unperturbed discharges. A large reduction in gross erosion (50%) was observed in the private flux region at the W sample for one specific toroidal phase of the RMP field.