Physics of the tau lepton


  • Jorge Portoles IFIC (U. Valencia - CSIC)



Phenomenology of the tau lepton


Within our present knowledge, the tau is the heaviest lepton and the only one decaying into hadrons, a fact that makes it the source of a very rich phenomenology. It represents the third family of leptons in the Standard Model, a feature that helps its classification but whose real meaning is not asserted yet. The tau lepton provides: i) a clean and unique environment to study both the hadronization of QCD currents, in an energy region populated by resonances, and the phenomenological determination of relevant parameters of the Model; ii) together with the muon, they have a very constrained flavour dynamics (in the absence of neutrino masses) due to an accidental global symmetry of the Standard Model. In consequence, the tau lepton brings an excellent benchmark for the study of QCD at low energies and, at the same time, for the search of new physics.


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How to Cite

Portoles J. Physics of the tau lepton. Supl. Rev. Mex. Fis. [Internet]. 2022 May 25 [cited 2022 Jul. 2];3(2):020715 1-11. Available from: