ETYM New Lat., from Greek meson middle, neut. of mesos, a., middle.
An elementary particle responsible for the forces in the atomic nucleus; a hadron with a baryon number of 0; SYN. mesotron.
A hadron made from an even number of quark constituents The basic structure of most mesons is one quark and one antiquark.
Unstable subatomic particle with a mass between that of an electron and a photon, found in cosmic radiation.
In physics, an unstable subatomic particle made up of two indivisible elementary particles called quarks. It has a mass intermediate between that of the electron and that of the proton, is found in cosmic radiation, and is emitted by nuclei under bombardment by very high-energy particles.
The mesons form a subclass of the hadrons and include the kaons and pions. Their existence was predicted in 1935 by Japanese physicist Hideki Yukawa.