Hyperon

In particle physics, a hyperon is any baryon containing one or more strange quarks, but no charm, bottom, or top quark.

Being baryons, all hyperons are fermions. That is, they have half-integer spin and obey Fermi–Dirac statistics. They all interact via the strong nuclear force, making them types of hadron. They are composed of three light quarks, at least one of which is a strange quark, which makes them strange baryons. Hyperons decay weakly with non-conserved parity.

Ξ−
+
π0

Notes:

It takes multiple flavor-changing weak decays for it to decay into a proton or neutron. Murray Gell-Mann's and Yuval Ne'eman's SU(3) model (sometimes called the Eightfold Way) predicted this hyperon's existence, mass and that it will only undergo weak decay processes. Experimental evidence for its existence was discovered in 1964 at Brookhaven National Laboratory. Further examples of its formation and observation using particle accelerators confirmed the SU(3) model.

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