Pseudoscalar meson (original) (raw)

In high-energy physics, a pseudoscalar meson is a meson with total spin 0 and odd parity (usually notated as JP = 0− ).Pseudoscalar mesons are commonly seen in proton-proton scattering and proton-antiproton annihilation, and include the pion (π), kaon (K), eta (η), and eta prime (η′) particles, whose masses are known with great precision. Among all of the mesons known to exist, in some sense, the pseudoscalars are the most well studied and understood.