The next lepton to be observed was the muon, discovered by Carl D.
The first charged lepton, the electron, was theorized in the mid-19th century by several scientists and was discovered in 1897 by J. However, according to certain theories, neutrinos may be their own antiparticle, but it is not currently known whether this is the case or not. For every lepton flavor there is a corresponding type of antiparticle, known as antilepton, that differs from the lepton only in that some of its properties have equal magnitude but opposite sign. Unlike quarks however, leptons are not subject to the strong interaction, but they are subject to the other three fundamental interactions: gravitation, electromagnetism (excluding neutrinos, which are electrically neutral), and the weak interaction. Leptons have various intrinsic properties, including electric charge, spin, and mass. Thus electrons are stable and the most common charged lepton in the universe, whereas muons and taus can only be produced in high energy collisions (such as those involving cosmic rays and those carried out in particle accelerators). The heavier muons and taus will rapidly change into electrons through a process of particle decay: the transformation from a higher mass state to a lower mass state. Electrons have the least mass of all the charged leptons. Μ) and the third is the tauonic leptons, comprising the tau ( τ − The first generation is the electronic leptons, comprising the electron ( e −Į) the second is the muonic leptons, comprising the muon ( μ − There are six types of leptons, known as flavours, forming three generations. Charged leptons can combine with other particles to form various composite particles such as atoms and positronium, while neutrinos rarely interact with anything, and are consequently rarely observed. Two main classes of leptons exist: charged leptons (also known as the electron-like leptons), and neutral leptons (better known as neutrinos). The best known of all leptons is the electron which governs nearly all of chemistry as it is found in atoms and is directly tied to all chemical properties. Leptons are involved in several processes such as beta decay.Ħ ( electron, electron neutrino, muon, muon neutrino, tau, tau neutrino)Ī lepton is an elementary particle and a fundamental constituent of matter. For other uses, see Lepton (disambiguation).