beta decay
Americannoun
noun
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A form of radioactive decay caused by the weak nuclear force, in which a beta particle (electron or positron) is emitted.
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◆ In beta-minus decay, a neutron in an atomic nucleus decays into a proton, an electron, and an antineutrino. The electron and antineutrino are emitted from the nucleus, while the proton remains. The atomic number of the atom is thereby increased by 1. The decay of Carbon-14 into Nitrogen-14, a phenomenon useful in carbon dating, is an example of beta-minus decay.
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◆ In beta-plus decay, a proton in an atomic nucleus decays into a neutron, a positron, and a neutrino. The positron and neutrino are emitted from the nucleus, while the neutron remains. The atomic number of the atom is thereby reduced by 1. The decay of Carbon-10 to Boron-10 is an example of beta-plus decay.
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See also W boson
Etymology
Origin of beta decay
First recorded in 1930–35
Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
Along this pathway across the nuclide chart, a common sequence involves beta decay of the parent nucleus followed by the release of two neutrons.
From Science Daily ● Mar. 13, 2026
Scientists have performed a new, more sensitive measurement of beta decay properties to hunt for a theorized feature of the weak nuclear force not currently included in the Standard Model.
From Science Daily ● Apr. 19, 2024
The prior year she had proved Enrico Fermi's theory of beta decay after more than a decade of attempts by others.
From Scientific American ● Mar. 16, 2023
They then counted the electrons from the beta decay of the fission fragments and measured the electrons’ energy spectrum.
From Science Magazine ● Jan. 11, 2023
This is different from beta decay, in which a neutron is transformed into a proton by the emission of an electron.
From "Big Science" by Michael Hiltzik
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Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.