Abstract
The mean lifetime of the τ lepton is measured in a sample of 25700 τ pairs collected in 1992 with the ALEPH detector at LEP. A new analysis of the 1-1 topology events is introduced. In this analysis, the dependence of the impact parameter sum distribution on the daughter track momenta is taken into account, yielding improved precision compared to other impact parameter sum methods. Three other analyses of the one- and three-prong τ decays are updated with increased statistics. The measured lifetime is 293.5±3.1± 1.7 fs. Including previous (1989–1991) ALEPH measurements, the combined τ lifetime is 293.7±2.7±1.6fs.
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ALEPH Collaboration. Measurement of the τ lepton lifetime. Z Phys C - Particles and Fields 70, 549–559 (1996). https://doi.org/10.1007/s002880050132
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DOI: https://doi.org/10.1007/s002880050132