The positron or antielectron is the antiparticle or the antimatter counterpart of the electron.
The positron has an electric charge of +1 e, a spin of 1/2, and has the same mass as an electron. When a low-energy positron collides with a low-energy electron, annihilation occurs, resulting in the production of two or more gamma ray photons
Cloud chamber photograph by C. D. Anderson of the first positron ever identified. A 6 mm lead plate separates the upper and lower halves of the chamber. The deflection and direction of the particle's ion trail indicate the particle is a positron
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