Neutron

Subatomic particle with no charge

A neutron is a subatomic particle, symbol n or n0, that has no electric charge, and a mass slightly greater than that of a proton. The neutron was discovered by James Chadwick in 1932, leading to the discovery of nuclear fission in 1938, the first self-sustaining nuclear reactor (Chicago Pile-1, 1942), and the first nuclear weapon (Trinity, 1945). Neutrons are found, together with a similar number of protons, in the nuclei of atoms.

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