K-meson

Key Stage 5

Meaning

A K-meson is a type of meson which has a strangeness of +1 or -1.

About K-mesons

K-mesons decay via the weak interaction to produce π-mesons. In this case strangeness is not conserved.

NB: You do not need to memorise the exact composition of a given K-meson. However, you should be able to determine a possible quark composition given the charge and strangeness of the meson and by remembering the properties of the up-quark, down-quark and strange-quark.

K-meson may consist of:

• Up-antistrange quark pair (\(K^+\)).
• Down-antistrange quark pair (\(K^0\)).
• Strange-antiup quark pair (\(K^-\)).
• Strange-antidown quark pair (\(\bar{K}^-\)).