Measurement of the Tau Lepton Lifetime with BaBar

The mean lifetime of the tau lepton is measured from the decay length distribution of 3-prong tau decays from e+e− collisions at the ϒ(4S) resonance. A data sample of 80.0 fb−1 collected with the BaBar detector at the PEP-II B Factory is used for this measurement. The measured tau lifetime is: ττ=289.40±0.91 (stat.)±0.90 (syst.) fs. All the results are preliminary.