Cross-Machine Empirical Validation of Macroscopic Multi-Sensor Flux-Asymmetry Precursors for Tokamak and Stellarator Disruption Mitigation

Predicting and mitigating catastrophic plasma disruptions remains the primary operational imperative for magnetic confinement fusion devices, including ITER and future power reactors. While classical single-fluid magnetohydrodynamics (MHD) enforces strict local magnetic solenoidality (∇·B = 0), discrete boundary diagnostic arrays operating on accelerating, turbulent plasmas register pronounced spatial flux asymmetries prior to a macroscopic current quench.In this work, we establish a unified continuum framework coupling compressible fluid mechanics with dynamic relativistic frame transformations (E = v × B and H = -v × D) expressed in identical volumetric force density units (N/m³). We demonstrate that localized plasma vorticity (∇ × v ≠ 0) and mode-locking during the growth of non-axisymmetric instabilities (e.g., m/n = 2/1 tearing modes) naturally induce a macroscopic spatial divergence proxy D_B ≡ ∇·B ≠ 0 across discrete poloidal sensor arrays, accompanied by an anti-phase electric divergence precursor D_E ≡ ∇·E.To empirically validate this dual-divergence precursor, an automated, double-blind detection protocol was deployed across four radically distinct magnetic confinement topologies: (1) TCABR (Brazil, conventional tokamak), yielding an average early-warning lead time of 0.234 ms (maximum 1.502 ms); (2) FAIR MAST (UK, mega-ampere spherical tokamak), expanding the mitigation window to over 7.16 ms; (3) NIFS LHD (Japan, 3D superconducting stellarator), achieving a 49.58% detection rate (468 shots) with lead times up to 199.95 ms (mean 124.58 ms); and (4) GOLEM (Czech Republic, mini-tokamak), proving 100% detection sensitivity (44/44 discharges) with lead times up to 10.23 ms, encompassing over half the discharge lifetime. These empirical results establish multi-sensor flux asymmetry as a universal, noise-resilient, and scale-invariant precursor metric for active disruption mitigation systems (such as Shattered Pellet Injection).