Evolution of the Plasmodynamic Structure of the Penning Discharge under Variation of Pressure and Magnetic Field Induction

Abstract

Numerical investigation of regularities in the variation of the electrodynamic structure of the Penning discharge in molecular hydrogen under variations in pressure from p = 0.5 to 5.0 mTorr and magnetic field induction in the range of B_x = 0.001–0.3 T is carried out using the diffusion-drift model which involves the nonlinear dependence of ion and electron drift velocities on the electric field strength and the Thomson coefficient of impact ionization of neutral particles by electrons at large reduced electric fields. As a result of the numerical simulation, configurations of gas-discharge plasma corresponding to different regimes of Penning discharge combustion have been found. In the pressure and magnetic field induction range under study, the transition between modes of weak and strong fields has been traced. In the transition region, regimes of Penning discharge combustion with the formation of nonstationary vortex structures of gas-discharge plasma in near-axis regions and, as a consequence, generation of pulse-periodic emission of ion beams from the meniscus of the discharge chamber have been revealed.