The antiparticle partner to the electron; symbol e+; mass and spin same as electron, but charge +1; discovered in 1932 by US physicist Carl Anderson and British physicist Patrick Blackett (18971974), by observing tracks left in cloud chambers by cosmic rays. It annihilates with electrons to give gamma rays, and is emitted by some radioactive sources, such as sodium-22. It is used in positron emission tomography in medicine, and in studies of the electron properties of solids.
For other uses, see Positron (disambiguation).
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Positron
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Composition:
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Elementary particle
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Family:
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Fermion
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Group:
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Lepton
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Generation:
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First
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Interaction:
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Gravity, Electromagnetic, Weak
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Antiparticle:
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Electron
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Theorized:
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Paul Dirac, 1928
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Discovered:
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Carl D. Anderson, 1932
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Symbol:
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β+
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Mass:
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9.1093826(16) × 10
0.510998918(44) MeV/c2
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Electric charge:
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1.602176462(63) × 10
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Spin:
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½
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The positron is the antiparticle or the antimatter counterpart of the electron.
The positron in fiction
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Antimatter
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Overview
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Annihilation
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Devices Particle accelerator Penning trap
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Antiparticles Positron Antiproton Antineutron Antimuon Antitauon Electron antineutrino Muon antineutrino Tau antineutrino
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Uses PET Fuel Weaponry
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Bodies ALPHA Collaboration ATHENA ATRAP CERN
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People Paul Dirac Carl Anderson
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The most famous use of the positron in fiction was Isaac Asimov's use in his robots' positronic brains. Quantum electrodynamics
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electron
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positron
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photon
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self-energy
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vacuum polarization
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vertex function
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Gupta-Bleuler formalism
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ξ gauge
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Ward identities
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Compton scattering
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Bhabha scattering
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Moeller scattering
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anomalous magnetic dipole moment
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positronium
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bremsstrahlung
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