Ion Heating and Flow Driven by an Instability Found in Plasma Couette Flow

We present the first observation of instability in weakly magnetized, pressure dominated plasma Couette flow firmly Hall regime. Strong currents couple to a low frequency electromagnetic mode that is driven by high-$\ensuremath{\beta}$ ($>1$) profiles. Spectroscopic measurements show heating (factor 3) cold, unmagnetized ions via resonant Landau damping process. A linear theory this derived predicts positive growth rates at finite $\ensuremath{\beta}$ and shows stabilizing effect very large $\ensuremath{\beta}$, line with observations.