The energy released by a nuclear explosion.


West Valley Demonstration Plant, the name of the vitrification plant for high-level radioactive wastes at West Valley, New York.


A radioactive isotope of hydrogen whose nucleus contains one proton and two neutrons.

TNT equivalent

The weight of TNT which would release the same amount of energy as a particular nuclear explosion. One ton of TNT releases approximately 1.2 billion calories (that is, 5.1 kiloJoules per gram). Nuclear explosions are usually measured in kilotons (KT) or megatons (MT).


A metric ton is 1,000 kilograms. This is approximately 2,200 pounds, and very nearly equal to a British ton (2,240 pounds). The U.S. tone is 2,000 pounds.

thermonuclear weapon

A nuclear weapon that gets a large part of its explosive power from fusion reactions.

sub-critical reactor

A nuclear reactor that is configured to operate with an external source of neutrons to supplement internally generated neutrons to maintain the chain reaction.

spontaneous fission

The spontaneous splitting of the nucleus into two new nuclei, generally with the emission of one or more neutrons and the release of energy.


A unit of equivalent absorbed dose equal to 100 rems.

specific activity

A measure of the radioactivity of a unit weight (generally one gram) of material.

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