Strange quark
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The strange quark is a second-generation quark with a charge of -(1/3)e and a strangeness of −1. It is the lightest of the quarks except for the up and down quarks, with a mass of somewhere between 80 and 130 MeV. The first strange particle (particle containing a strange valence quark) was discovered in 1947, with the identification of the kaon, but the strange quark itself was not identified until Gell-Mann and Zweig developed the quark model in 1964.
Hadrons containing strange valence quarks
Hadrons containing strange valence quarks include the following:
- Kaons are mesons containing a strange quark (or its antiparticle) and an up or down quark.
- The η and η' flavorless mesons are linear combinations of several quark-antiquark pairs, including the strange-antistrange.
- The φ flavorless meson is pure strange-antistrange.
- Strange baryons are known as hyperons: the Σ and Λ have one strange quark, the Ξ two, and the Ω three.
See also
- Strange matter
- Strange star
- Strangelet
| Particles in physics - elementary particles | [http://encycl.opentopia.com/ edit ] |
| Fermions: Quarks: (Up · Down · Strange · Charm · Bottom · Top) | Leptons: (Electron · Muon · Tau · Neutrinos) | |
| Gauge bosons: Photon | W and Z bosons | Gluons | |
| Not yet observed: Higgs boson | Graviton | Other hypothetical particles | |
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