Phi meson

Phi meson ( φ )

The φ -meson, also Phi - meson is a meson, which consists of a strange quark and the corresponding anti- quark and spin 1 has ( Vektormeson ).

Since the φ -meson inter alia, containing a strange quark, it is one of the strange particles. Since it is composed of a quark and its antiquark, it is beyond a quarkonium.

Description

In the quark model, the φ - and ω -meson mixtures of the three quark- antiquark states uu, dd and ss the Up, Down, and strange quarks. Both mixtures each have a hypercharge and isospin one and are in the multiplet of vector mesons in the same place as the neutral ρ - meson.

The three mutually orthogonal linear combinations of the above-mentioned Quark- antiquark states are thereby identified as follows:

The physical (mass) states φ and ω arise again as linear combinations of and:

The thus introduced mixing angle has an experimental value, which corresponds to about 39 ° almost the ideal mixing angle of ≈ 35.3 ° (). Thus, the φ -meson consists almost exclusively of a Strange anti - strange quark pair, and the flavor wave function can be written as

The φ -meson was first detected in 1963 at the Lawrence Radiation Laboratory in kaon -proton reactions.

Decay channels

φ - meson decay with the strong force. The decay takes place mainly in two kaons, either the charged Κ / Κ ( 48.9 %) or the neutral Κ0L / Κ0S ( 34.2 %), and to a lesser extent in either a ρ -meson and a pion or into three pions ( 15.32 %). The latter two decay channels in meson without strangeness supposed to be dominant due to their higher Q value, but are suppressed by the OZI rule.

Special

Due to the mixing effects of the pseudoscalar η mesons, the φ -meson is the lightest meson, which consists of a Strange anti - strange quark pair.