type of radioactivity in which an unstable atomic nucleus dissipates energy by gamma emission, producing gamma rays.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
A radioactive process in which an atomic nucleus loses energy by emitting a gamma ray (a stream of high-energy photons). When an element undergoes gamma decay its atomic number and mass number do not change.
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