Definition of muon in English:

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Pronunciation: /ˈmjuːɒn/


An unstable subatomic particle of the same class as an electron (a lepton), but with a mass around 200 times greater. Muons make up much of the cosmic radiation reaching the earth’s surface.
Example sentences
  • The proton and the neutron are baryons; the electron, the muon, and the neutrino are leptons; whilst the pions are mesons.
  • These objects also produce high-energy massive particles such as electrons, muons, protons and anti-protons.
  • Comsic rays are very high energy particles which strike the Earth's atmosphere and produce spectacular showers of billions of electrons, muons, and other particles.



Example sentences
  • For muonic atoms, the Bohr-Weisskopf effect can account for half of the hyperfine structure interaction.
  • The nuclear interaction in muonic molecules can be treated as a perturbation using the smallness of the nuclear scattering amplitude in comparison with the molecular scale.
  • Understanding muonic atom formation and the cascade process to the ground state is important, since they affect muon transfer from excited states, as well as the creation of hot atoms via acceleration.


1950s: contraction of mu-meson; the particle, however, is no longer regarded as a meson.

For editors and proofreaders

Line breaks: muon

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