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beta decay

American  

noun

Physics.
  1. a radioactive process in which a beta particle is emitted from the nucleus of an atom, raising the atomic number of the atom by one if the particle is negatively charged, lowering it by one if positively charged.


beta decay British  

noun

  1. Also called: beta transformation.   beta process.  the radioactive transformation of an atomic nucleus accompanying the emission of an electron. It involves unit change of atomic number but none in mass number

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

beta decay Scientific  
  1. A form of radioactive decay caused by the weak nuclear force, in which a beta particle (electron or positron) is emitted.

  2. ◆ 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.

  3. ◆ 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.

  4. 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.

See Examples For:

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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