Strange quark

The strange quark is a second-generation quark with a charge of -(1/3)e and a strangeness of −1. It is the third lightest quark after 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.

Additional recommended knowledge

Daily Visual Balance Check

Daily Sensitivity Test

Don't let static charges disrupt your weighing accuracy

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