The
muon (; from the
Greek letter
mu (µ) used to represent it) is an
elementary particle similar to the
electron, with
electric charge of -1
e and a , but with a much greater mass . It is classified as a
lepton, together with the
electron (mass ), the
tau (mass ), and the three
neutrinos (electron neutrino , muon neutrino and tau neutrino ). As is the case with other leptons, the muon is not believed to have any sub-structure—that is, it is not thought to be composed of any simpler particles.