Christofilos effect

The Christofilos Effect refers to the entrapment of charged particles along magnetic lines of force that was first predicted in 1957 by Nicholas Christofilos. Christofilos suggested the effect had defensive potential in a nuclear war, with so many beta particles (electrons) becoming trapped that warheads flying through the region would see electrical currents so great that their trigger electronics would be damaged. The concept that a few friendly warheads could disrupt an enemy attack was so promising that a series of new nuclear tests was rushed into the schedule before a testing moratorium came into effect in late 1958. These tests demonstrated that the effect was not nearly as strong as predicted, and not enough to damage a warhead. However, the effect is strong enough to be used to black out radars and disable satellites.

Among the many different types of energy released by a nuclear explosion are a large number of beta particles, or high energy electrons, created by the nuclear fission reactions used in a typical nuclear bomb design. Because these particles are charged, they induce electrical currents into atoms as they pass them by at high speed, causing the atom to ionize while causing the beta to slow slightly. In the lower atmosphere this reaction is so powerful that the betas slow to thermal speeds within a few tens of meters at the most, but at high altitude they are free to travel long distances.

If a bomb is exploded above the atmosphere, those betas travelling downward will continue to do so until the atmosphere reaches a critical density, typically between 50 and 60 km. This causes a large disk of ionized air to form under the explosion point, causing nuclear blackout. A similar number, travelling upwards, will be lost to space. The Christofilos effect concerns those betas travelling roughly parallel to the Earth's magnetic field at the point of explosion. These betas, being charged, become trapped within the field and begin to travel north and south along the lines of force. Since these are curved and meet the ground near the north and south magnetic poles, these particles eventually hit the atmosphere as well, causing similar ionization disks to form.

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