Strangeness

In particle physics, strangeness S is a quantum number needed to describe certain short-lived particles. It is defined as the number of strange anti-quarks overline{s} minus the number of strange quarks s in a particle.

Related Topics:
Particle physics - Particles - Strange quark - Particle

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:S = n_{overline{s}} - n_s

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The reason for this unintuitive definition is that the concept of strangeness was defined before the existence of quarks was discovered, and for consistency with the original definition the strange quark must have strangeness -1, and the anti-strange quark must have strangeness +1.

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For all the quark flavor quantum numbers (strangeness, charm, topness and bottomness) the convention is that the flavor charge and the electric charge of a quark have the same sign. With this, any flavor carried by a charged meson has the same sign as its charge.

Related Topics:
Charm - Topness - Bottomness - Meson

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