eta-meson

subatomic particle

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Last updated

June 26, 2026

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The eta meson is an uncharged subatomic particle with zero spin. It has a mass approximately 1074 times that of an electron and decays rapidly, primarily into pions.1

The eta meson is a type of meson, which is a particle composed of a quark and an antiquark. Mesons are sensitive to the strong force and are all unstable, with short lifetimes. The existence of the eta-meson was predicted by the Eightfold Way model and later discovered in 1962.2

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meson
…and subsequent discovery of the eta-meson (1962). Some years later the decay rate of the pi-meson into two photons was used to support the hypothesis that quarks can take on one of three “colours.” Studies of the competing decay modes of K-mesons, which occur via the weak force, have led…
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…and subsequent discovery of the eta-meson (1962). Some years later the decay rate of the pi-meson into two photons was used to support the hypothesis that quarks can take on one of three “colours.” Studies of the competing decay modes of K-mesons, which occur via the weak force, have led…
Read More