Abstract
This chapter discusses the properties of tau lepton. LEP tau lepton is produced either in Z 0 boson decay or in two photon collision. The tau lepton lifetime, produced during two photon collision, has been measured by DELPHI using three different methods. Two of them are based on one-prong decays and one is based on three-prong decays. Tau decays provide a direct limit on the tau neutrino mass. The limit is derived from the two-dimensional distribution of the invariant mass and energy of tau decay products. Besides Z 0 decay, tau pairs are produced at LEP in the collisions of two virtual photons emitted by electron and positron. DELPHI and L3 have analyzed LEP2 data to extract the cross-section of the process. The obtained limits are competitive with the world best limits obtained from measurement of e + e − → ττγ process. New limit has been set on the tau neutrino mass from the study the endpoint of the τ → 5 π decay spectrum by DELPHI.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
