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J/psi particle

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noun \ˌjā-ˈsī-, -ˈpsī-\

Definition of J/psi particle

: an unstable neutral fundamental particle of the meson group that has a mass about 6000 times the mass of an electron —called also J particle, J/psi, psi particle

First Known Use of j/psi particle

1977

Learn More about j/psi particle

Britannica.com: Encyclopedia article about J/psi particle

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