Each pion consists of a quark and an antiquark and is therefore a meson. Some composite particles are vector bosons, for instance any vector meson (quark and antiquark). Protons and neutrons are examples of baryons; pions are an example of a meson. In 2013 LHCb announced discovery of CP violation in strange B meson decays. A large number of CP violation processes in B meson decays have now been discovered. In modern terminology, this makes the muon a lepton, and not a meson. Soon, his focus turned to particle physics and the developing puzzle of K meson decays. Due to its mass, it was initially categorized as a meson rather than a lepton. He predicted the beta decay of a pi meson. The charged rho meson has a very short lifetime, about . His work predicted many later finds, which include the neutron, meson and neutron star. The other members of this octet are the four kaons and the eta meson. A theory called Vector Meson Dominance (VMD) was developed to explain this effect. In 1963, Salam published his theoretical work on the vector meson. There is a recent claim about the mass of the heavy meson B .