New probe techniques make it possible to measure the E_θ fields, as well as the associated Φ(θ), directly in the unbifurcated radial zone 0.8 < r/a < 0.95 (in H-mode the bifurcated zone occurs over 0.95 < r/a < 1). These field measurements are in agreement with Mach probe and energy analyzer measurements of flows and potentials when the flux tubes are interrupted. The authors find that in the confined region (r/a < 0.95), the E_θ (poloidal asymmetry) driven convective flux is the dominant pinch mechanism. The dominant 2-D topological characteristics of the H-mode and its non-local nature play a role in improving the roughness of the density surfaces throughout the profile. Extension of the findings about the m = l poloidal shock suggests that "core H-modes", observed in JT-60U and some other tokamaks, may be accompanied by density asymmetries indicative of rapid poloidal rotation. Under these characteristically peaked profile conditions the pressure is not always a flux function.
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