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A Neutron

Neutrons are uncharged particles found within atomic nuclei. Neutrons were discovered by James Chadwick in 1932.

Experiments done at the Stanford Linear Accelerator Center in the late 1960's and early 1970's showed that neutrons are made from other particles called quarks. Neutrons are made from one 'up' quark and two 'down' quarks.

Particle Data

SymbolMassHalf-lifeChargeSpinQuark Content
n939.6 MeVin nuclei: stable01/2udd
free: 10.18 minutes

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