radioactive decay

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radioactive decay

the disintegration of the nucleus of an unstable nuclide by the spontaneous emission of charged particles, photons, or both.

radioactive decay

The continual loss of energy by radioactive substances. Disintegration of the nucleus by the emission of alpha, beta, or gamma rays eventually results in the complete loss of radioactivity. The time required for some materials to become stable may be minutes and, for others, thousands of years.
See: half-life
See also: decay


characterized by radioactivity.

radioactive decay
spontaneous decomposition of the nuclei of the atoms of radioactive substances. Measured as the proportion of the atoms in a radionuclide that decompose per unit of time, usually stated as the half-life of that particular isotope.
radioactive fallout
dissemination of radioactive substances through the atmosphere and deposition on the environment generally; causes radiation injury.
radioactive isotope
radionuclide. A radioactive nuclide, e.g. radioactive iodine or strontium.
radioactive tracer
see radioactive tracer.
References in periodicals archive ?
Let me stress that I am not proposing at this time that nuclear decay rates actually do increase over time.
The finding suggests that telltale patterns of nuclear decay within black-market ivory may help conservationists track down hotspots of illegal elephant hunting and stem the decline of the endangered pachyderm.
The hard X-rays found in these discoveries are supposed to come ultimately from processes of nuclear fusion and nuclear decay that between them make the heavier chemical elements.
Because free neutron decay is unencumbered by the many-nucleon effects present in all other nuclear decays, measurements of the parameters that describe neutron decay can be related to the fundamental weak couplings in a straightforward fashion.
Harriet Brooks, discoverer of the recoil of the radioactive atom and of successive nuclear decays, was honoured recently in Ottawa, ON, by being inducted into the Canadian Science and Technology Hall of Fame.
For example: Are the four basic forces of nature--the electromagnetic force, the weak force that controls nuclear decays, the strong force that holds atomic nuclei together, and gravity--variations of a single, more fundamental force?
Nuclear decays of thorium, uranium, and the isotopes into which those elements transform give off antineutrinos.

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