# A Precise Measurement of the Tau Lepton Lifetime

Abstract : The tau lepton lifetime has been measured using three different methods with the DELPHI detector. Two measurements of one-prong decays are combined, accounting for correlations, giving a result of \tau_\tau = 291.8 \pm 3.3 \mbox{ (stat.)} \pm 2.0 \mbox{(sys.) fs} while the decay length distribution of three-prong decays gives the result \tau_{\tau} = 286.7 \pm 4.9 \mbox{ (stat.)} \pm 3.3 \mbox{ (sys.) fs}. Combining the results presented here with previous DELPHI measurements, we get \tau_{\tau} = 291.4 \pm 3.0 fs and find that the ratio of the coupling constant for tau decay relative to that for muon decay is 0.990 \pm 0.009, compatible with lepton universality.
Document type :
Journal articles

Cited literature [5 references]

http://hal.in2p3.fr/in2p3-00009588
Contributor : Sylvie Flores Connect in order to contact the contributor
Submitted on : Tuesday, February 9, 1999 - 2:14:26 PM
Last modification on : Friday, September 10, 2021 - 1:50:05 PM
Long-term archiving on: : Tuesday, June 2, 2015 - 12:00:41 PM

### Identifiers

• HAL Id : in2p3-00009588, version 1

### Citation

P. Abreu, W. Adam, T. Adye, E. Agasi, I. Ajinenko, et al.. A Precise Measurement of the Tau Lepton Lifetime. Physics Letters B, Elsevier, 1996, 365, pp.448-460. ⟨in2p3-00009588⟩

Record views