Simulation of Close Electric Fields From Fast M-Component Considering a Wire-Exploded Luminous Channel in Rocket-Triggered Lightning

The study presents the close electric fields radiated by fast M-components associated with two scenarios in lightning: an elevated tall object and a wire-exploded luminous channel. The assumptions are assumed that when the downward incident wave meets the wire-exploded luminous channel, one round reflection (downward and upward) among the channel is assumed, and then, it propagates upward directly to cloud. The current expressions and current distribution for both scenarios are presented. The influences of the wire-exploded luminous channel on M-component electric fields at close distance are on the positive excursion at late-time response, while the initial negative peak is notably affected associated with the scenario of a tall tower. The influences of wave speed, reflection rounds, different close distances, and heights of the struck tower or the wire-exploded luminous channel are discussed in relation to the tall tower or the wire-exploded luminous channel. This study is meaningful to understand the lightning M-component mechanisms, specifically, by means of the measurement and reproduction of M-component electric fields at close distance.