Gamma ray

Penetrating form of electromagnetic radiation

A gamma ray, also known as gamma radiation (symbol γ), is a penetrating form of electromagnetic radiation arising from high-energy interactions like the radioactive decay of atomic nuclei or astronomical events like solar flares. Lower energy gamma radiation overlaps the upper end of X-ray radiation; they are distinguished by their different origins. Gamma ray photons have photon energy at the lower end from 104 eV to 107 eV; ultra-high-energy gamma rays have energies over 1014 eV. Paul Villard, a French chemist and physicist, discovered gamma radiation in 1900 while studying radiation emitted by radium.

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