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TAU LEPTON MASS SERIES

When a single tauon decays, it is the only lepton that can decay into hadrons (things made of quarks). Also, τ + and τ – can annihilate each other in a form of decay. Tauons themselves are unstable, and can decay. Since antimatter has the opposite of charge of regular matter, anti-tauons have a charge of +1, and can be written as τ +. Tau have a charge of -1, and can be written as τ –. Like the other two basic leptons, tauons have a neutrino named after them (the tau neutrino). However, they are very important in the decay of subatomic matter. Since they only live for 2.9x10 –13 seconds, they do not have a significant role in the regular world. This is because they have about 3,500 times as much mass as electrons, and about 17 times as much mass as muons. Tau leptons can be thought of as very heavy electrons, as they are both leptons. This means that they are believed to be so small that they can not be divided any more. Journal of Physics G 33.Tau (τ) leptons (aka tauons, tau particle) are one of the very small elementary particles. Perl et al, "Evidence for Anomalous Lepton Production in e +-e - Annihilation" Phys. The latter was awarded his share of the prize for detecting the neutrino. Martin Perl shared the 1995 Nobel Prize for physics with Frederick Reines. Work done at DESY-Heidelberg, and with the Direct Electron Counter (DELCO) at SPEAR, subsequently established the mass and spin of the tau. This was difficult to verify, because the energy to produce the τ +τ − pair is similar to the threshold for D meson production. It was proposed that this event was the production and subsequent decay of a new particle pair: However, no other muons, electrons, photons, or hadrons were detected. The need for at least 2 undetected particles was shown by the inability to conserve energy and momentum with only one. " We have discovered 64 events of the formįor which we have no conventional explanation." They did not detect the tau lepton directly, but rather discovered anomalous events: They could detect and distinguish between leptons, hadrons and photons. Their equipment consisted of SLAC's then-new e +-e − colliding ring, called SPEAR, and the LBL magnetic detector.

TAU LEPTON MASS SERIES

The tau lepton was detected in a series of experiments between 19 by Martin Lewis Perl with his colleagues at the SLAC-LBL group.

17.36% for decay into a tau neutrino, muon and muon neutrino.

17.84% for decay into a tau neutrino, electron and electron neutrino.

The branching ratio of the common tau decays are: Since tau-like lepton number is conserved in weak decays, a tau neutrino is created when a tau lepton decays to a muon or electron. Like the other decay modes of the tau lepton, the hadronic decay is through the weak interaction. The tau is the only lepton that can decay into hadrons-the other leptons do not have the necessary mass. The tau lepton and its antiparticle carry the same electric charges as the electron and positron, respectively. Also, like the electron and muon, the tau has a spin of 1/2. Like the electron and muon, the tau lepton appears to be pointlike no structure has been detected, and if there is any, it would have to be on a scale of less than 10 −18 meters. It is the third generation counterpart of the electron (1st generation) and the muon (2nd generation).

The tau lepton belongs to the 3rd generation of leptons.