Updated measurement of the tau lepton lifetime

TL;DR

This paper reports a new measurement of the tau lepton's mean lifetime using three analysis methods on data collected with the ALEPH detector, resulting in a precise average value consistent with previous measurements.

Contribution

It provides an updated and more precise measurement of the tau lepton lifetime based on a large data sample and multiple analysis techniques.

Findings

Tau lepton lifetime measured as 290.1 fs

Three analysis methods yield consistent results

Measurement improves precision over previous estimates

Abstract

A new measurement of the mean lifetime of the tau lepton is presented. Three different analysis methods are applied to a sample of 90000 tau pairs, collected in 1993 and 1994 with the ALEPH detector at LEP. The average of this measurement and those previously published by ALEPH is tau_tau = 290.1 +- 1.5 +- 1.1 fs.