Diffusion of Antiparallel Bias Magnetic Field during the Initial Stages of a Theta-Pinch

Abstract

In a study of the early stages of a theta pinch in reversed bias magnetic field, it has been found experimentally that some of the bias flux is lost before the start of the implosion. The loss is a consequence of the hydromagnetic expansion of plasma and trapped field that occurs while the driving field reverses polarity. The amount of diffusion depends on the magnitude of the bias field relative to a certain critical field.