Simulations Of Fast Magnetic Field Penetration Into A Plasma

Abstract

Fast magnetic field penetration into plasmas has been hypothesized as a possible explanation for the operation of plasma opening switches. The authors have begun an in-depth numerical study of the behavior of plasma opening switches (POS),a nd relevant experimental results. Simulations using the 2-1/2 dimensional PIC codes OOPIC, MAGIC, and ISIS are compared with theory. Because of the difficulty in applying and comparing PIC simulations to actual POS experiments, the numerical work is at present concerned with validating the more modest scenarios predicted by theory, e.g., the penetration skin depth of the magnetic field. The state-of-the-art graphical user interface of OOPIC is especially convenient for observing the field penetration as a real-time movie. A review of previous experiments (NRL, Weizmann, etc.) will be examined to indicate if the phenomenon of fast magnetic field penetration into plasmas can account for some experimental observations. Experimental scenarios, e.g., the direction of the density gradients, values of the plasma collision frequency, electron orbits, etc. in a typical POS are discussed.