Predictive outlook for experiments resolving prompt vs local redeposition of high-Z materials in tokamaks

• DOI: 10.1088/1361-6587/adb64a
• Publication Date: 2025-02-14T22:51:16Z
• Authors: D C Easley; C A Johnson; A Diaw; T R Younkin; D C Donovan; E A Unterberg; S Abe

Abstract High-Z plasma facing components redeposit within the sheath through a combination of two distinct mechanisms: prompt (or geometric-driven) and local (or sheath-driven) redeposition. Experimental efforts are needed to determine the leading-order parameters influencing prompt-vs-local trade-off, which sets the fraction of material entering the scrape-off layer. In preparation for such experiments, leading-order parameters are isolated within the PYEAD-RustBCA-GITR coupled net erosion code using Sobol’ sensitivity analysis. Then, experiments resolving prompt-vs-local trade-off under variation of these leading-order parameters are proposed using an isotopic coupon design with multifaceted diagnostic coverage. The measurability of these experiments is evaluated using synthetic diagnostics.