A Simulation Of The Space-time Dependent Electromagnetic Effect Resulting From High-altitude Nuclear Explosions

High–altitude nuclear explosion effects analysis, including additional ionization and EMP, which will disable electrical equipments, communications, and control systems, is presented in this paper.The paper is based on the basic physical process of high-altitude nuclear explosions, combined with the existing academic results, tidied up the related computation formula, and a computer program is also made to simulate the electromagnetic effect of the high-altitude nuclear explosions. When photons released by high-altitude nuclear explosions interact with air molecules they produce an ionization of the atmosphere, and the densities of ion and electron will be changed due to the photoionization, atom adsorption, and recombination effects. When Compton current and secondary current interact with the asymmetry geomagnetic field for different atmosphere density they result in intense EMP signals.A resolution of the Ionization-Recombination equations adopting the Gear method and Runge-Kutta method is presented in this paper to predict the ionization of the atmosphere for different height and position, including the maximum density points of electron and ion in space-time and their relative diagram. A simplified Compton current model which enables the resolution of the Maxwell equations is used in the paper to predict the primary and secondary currents. A simulation of time-dependent EMP generated by high-altitude nuclear explosions using the finite-difference time-domain (FDTD) method is presented, and the maximal magnetic intensity and EMP waveforms are included.