radioactive decay


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Related to radioactive decay: alpha decay, half life, radioactivity

radioactive decay

(ray-dee-oh-ak -tiv) The spontaneous transformation of one atomic nucleus into another with the emission of energy. The energy is released in the form of an energetic particle, usually an alpha particle, beta particle (i.e. an electron), or positron, sometimes accompanied by a gamma-ray photon. The unstable isotopes of an element that can undergo such transformations are called radioactive isotopes, or radioisotopes. The emission of a particle from the nucleus of a radioisotope results in the production of an isotope of a different element, as in the beta decay of carbon–14 to nitrogen–14 or the alpha decay of radium–226 to radon–222. The isotope produced is itself often radioactive.

The average time taken for half a given number of nuclei of a particular radioisotope to decay is the half-life of that radioisotope; values range from a fraction of a second to thousands of millions of years. See also radiometric dating.

radioactive decay

[¦rād·ē·ō′ak·tiv di′kā]
(nuclear physics)
The spontaneous transformation of a nuclide into one or more different nuclides, accompanied by either the emission of particles from the nucleus, nuclear capture or ejection of orbital electrons, or fission. Also known as decay; nuclear spontaneous reaction; radioactive disintegration; radioactive transformation; radioactivity.
References in periodicals archive ?
In literature survey, radioactive decay is a random process and follows Poisson distribution, which is one of the discrete distributions.
The upward conduction of heat generated by radioactive decay within the over-thickened fertile lithospheric mantle will cause the increasing of temperature in the deep crust and the shallow mantle, and results in the decrease of seismic velocity in the shallow mantle, which is observed in the north part of Tibet plateau.
This interruption of neutrinos, due to the nucleons of Jupiter scattering and inelastically capturing some small, but non-trivial, proportion of particles and/or radiation causes a decrease in radioactive decay rate because of the consequent decrease in the particle flux transferring momentum to the nuclei of Po-210.
By measuring geoneutrinos, scientists hope to figure out how radioactive decay helps heat Earth.
However, radioactive decay is entirely different: there is no distribution of atomic weight of the decaying nucleus.
This phenomenon was later utilized by many scientists, including Otto Hahn and Lise Meitner, to separate daughter products in radioactive decay sequences, and hence identify new isotopes.
Here are two activities to help you better visualize the concept of radioactive decay and half-life.
The distribution of batting scores in Cricket shows an exponentially decreasing pattern similar to the radioactive decay curve.
For extraordinarily slow processes, like the evolution of the atmosphere, they use radioactive decay.
Humans are exposed to radiation from various sources, such as medical or dental procedures, radioactivity in the air, food and drink, radioactive decay in rocks and soil and high levels of cosmic radiation during air travel.
Since bullets are made of lead, it would shield against the radioactive decay associated with these isotopes, and any radiation hazard is pretty much secondary to the primary trauma of the gunshot wound itself.
Radon is produced from radioactive decay of uranium that occurs naturally in rocks and soil.