Electromagnetic Signals Produced by Low-Altitude Nuclear Explosions
A discussion of electromagnetic signals from nuclear explosions. As they appear at great distances, their general nature is reasonably well understood. Near the explosions, however, in the region ionized by the gamma rays, the electromagnetic phenomena have not been so well explored experimentally or so well understood theoretically. This memorandum bears on the phenomena in this near-in region. Specifically, a simplified model of the explosion is treated analytically. It assumes that the explosion takes place at a height h above an infinitely conducting ground, that the ambient air has a uniform and constant conductivity, and that the explosion is approximated as a point source of gamma rays. This model is solved analytically for the magnetic field at any point about the explosion. Some numerical results illustrate the time and space variation of the magnetic field.