Hyperon

A hyperon is a classification of sub-atomic particle, defined as a baryonic (and hence hadronic) fermion with non-zero strangeness.

All hyperons have half-integer spin and are all fermions. They all interact with the strong nuclear force, making them types of hadron. They are composed of three quarks, at least one of which is a strange quark, which makes them effectively strange baryons. Hyperons decay into a proton or neutron and a meson in 10^−10 to 10^−8 seconds. If they decay into a neutron, this further decays into a proton. They are classified through the quark model.

The Ω− has strangeness −3, so it takes three flavor-changing weak decays for it to decay into a proton or neutron. One such three-step decay was observed in a cosmic ray experiment, but it was not until other Ω− particles were produced and observed using particle accelerators that the model was considered confirmed.