Flute Instabilities in Two-Dimensional Simulations of Strongly Inhomogeneous Theta-Pinch Plasmas

Particle simulations initialized with inhomogeneous, self-consistent Vlasov equilibria that model theta pinches in the implosion and post-implosion phases have revealed a strongly unstable flute mode for $T_i>T_e$. Frequencies and wavelengths are in good agreement with the linear theory of the lower-hybrid-drift instability. Results agree with quasilinear estimates of heating rates and anomalous resistivity during the initial stages of the instability. The nonlinear saturation of the turbulence is consistent with ion trapping.