Numerically investigation of electromagnetic field with fireball formation

Summary form only given. Kapitza proposed a theory of ball lightning (1995). He suggested that ball lightning is formed at regions where intensity of radio waves, produced by thunderstorms, become highest by their interference. Ohtsuki and Ofuruton produced plasma fireballs by microwave interference at normal atmospheric pressure (1991). Their Experiment was based on Kapitza´s model. They used a cylindrical cavity in which microwaves interfered. Interference between a propagating wave and a reflected wave should make a standing wave in the cavity, and there should be theoretically some antinodes at which the electric field is strongest. Therefore, fireballs should be produced at these antinodes simultaneously. However, only one plasma fireball was observed in the cavity. The diameter of the experimental fireball is about 3 cm. It is much smaller than the cavity. The localized plasma fireball in the cavity should modify the standing wave, because it has electric conductivity. Furthermore the modified electromagnetic wave should influence the production of fireballs. In this paper the authors numerically calculate the mode of electromagnetic field modified by the formation of a fireball. They explain about the relation between the fireball and the electromagnetic field.