ELECTROMAGNETIC RADIATION FROM A NUCLEAR EXPLOSION IN SPACE

Abstract : The gamma rays from a nuclear explosion in space Compton scatter electrons near the surface of the device or in a surrounding material shield. The scattered electrons leave the surface and are accelerated back toward it by the positively charged matter. Provided they are asymmetrically distributed, the accelerating electrons radiate an electromagnetic signal. The electron motions are analyzed, the electromag netic signal is estimated, and its detectability is discussed. For a typical nuclear explosion, the electromagnetic signal is independent of the yield and contains frequencies up to 10 to 100 megacycles per second and thus will penetrate the ionosphere. Taking into account dispersion by the ambient interplanetary plasma (approximately equal to 10 sq. electrons/cc), the peak electric field strength at a distance R kilometers from the explosion is approximately equal to 10 to the 4th power R exp (-3/2) volts/ meter. The pulse length is approximately equal to 10 to the minus 10 power R sec. If only background cosmic noise limits detectability of the signal, the maximum detectable range is about 10 to the sixth power km.