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A subatomic particle of mass and charge equal to the electron but of opposite (that is, positive) charge.
Synonym(s): positive electron
positron/pos·i·tron/ (poz´ĭ-tron) the antiparticle of an electron; a positively charged electron.
a positively charged particle emitted from neutron-deficient radioactive nuclei; the antiparticle of an electron.
A subatomic particle of mass and charge equal to the electron but of opposite (i.e., positive) charge.
One of the small particles that make up an atom. A positron has the same mass and amount of charge as an electron, but the positron has a positive charge.
Mentioned in: Positron Emission Tomography (PET)
the antiparticle of the electron. When a positron is emitted by a radionuclide it combines with an electron and both undergo annihilation, producing two 511 keV gamma rays traveling in opposite directions. This effect is used in positron emission tomography (PET).