Advancing technologies for high-resolution spatial and temporal measurements of macroscopic stellarator flows

Stellarators, together with tokamaks, represent the two mainstream approaches to realizing fusion energy via toroidal magnetic confinement of highly ionized gases - plasmas - at extremely high temperatures. Improving our understanding of how macroscopic flows impact equilibrium and dynamics in stellarators closes a significant knowledge gap and is necessary to advance the physics basis of stellarators as a fusion pilot plant (FPP) concept. This is especially critical for the US stellarator design program, in both the public and private sectors, where stellarator FPP concepts are based almost exclusively on leveraging quasisymmetries. With this submission we invite the community to consider how the need for improving physics understanding of flows in advanced stellarators can serve as a catalyst for diagnostic and measurement innovation. This includes the identification of synergies with on-going technology development activities as well as opportunities to leverage new and emerging capabilities that may stem from hardware improvements and software, for example, application of AI/ML and workflow integration and management.