Eta Meson

Eta Meson

The eta (η) and eta prime meson (η′) are mesons made of a mixture of up, down and strange quarks and their antiquarks. The charmed eta meson (η
c) and bottom eta meson (η
b) are forms of quarkonium; they have the same spin and parity as the light eta but are made of charm quarks and bottom quarks respectively. The top quark is too heavy to form a similar meson (top eta meson, symbol η
t), due to its very fast decay.