radioactive decay(redirected from Activity (radioactivity))
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1. Spontaneous disintegration of a radionuclide with the emission of energetic particles or radiation, such as alpha or beta particles or gamma rays.
2. An instance of such disintegration.
(Nuclear Physics) disintegration of a nucleus that occurs spontaneously or as a result of electron capture. One or more different nuclei are formed and usually particles and gamma rays are emitted. Sometimes shortened to: decay Also called: disintegration
The spontaneous breakdown of a radioactive nucleus into a lighter nucleus. Radioactive decay causes the release of radiation in the form of alpha particles, beta particles, or gamma rays. The end result of radioactive decay is the creation of a stable atomic nucleus.
The decrease in the radiation intensity of any radioactive material with respect to time.
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|Noun||1.||radioactive decay - the spontaneous disintegration of a radioactive substance along with the emission of ionizing radiation|
alpha decay - radioactive decay of an atomic nucleus that is accompanied by the emission of an alpha particle
beta decay - radioactive decay of an atomic nucleus that is accompanied by the emission of a beta particle
nuclear reaction - (physics) a process that alters the energy or structure or composition of atomic nuclei