Definition of positron
: a positively charged particle having the same mass and magnitude of charge as the electron and constituting the antiparticle of the electron —called also antielectron
Recent Examples of positron from the Web
Scan The RefleXion machine’s positron emission tomography (PET) scanners show the hyperactive metabolic activity of tumors. 3.
But in reality, antimatter is really no different than regular matter, except that antimatter atoms have positrons instead of electrons and antiprotons instead of protons.
One involves a kind of brain scan known as positron emission tomography, or PET, while the other requires a spinal tap.
Because matter and antimatter annihilate each other on contact, antimatter positrons will be continuously produced on location by decay of the radioactive isotope potassium-40.
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Origin and Etymology of positron
positive + -tron (as in electron)
First Known Use: 1933See Words from the same year
POSITRON Defined for English Language Learners
Definition of positron for English Language Learners
physics : a very small particle of matter that has a positive charge of electricity and that travels around the nucleus of an atom
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