Measurement of the τ lifetime at SLD

Abstract

A measurement of the lifetime of the \ensuremath{\tau} lepton has been made using a sample of 1671 ${\mathit{Z}}^{0}$\ensuremath{\rightarrow}${\mathrm{\ensuremath{\tau}}}^{+}$${\mathrm{\ensuremath{\tau}}}^{\mathrm{\ensuremath{-}}}$ decays collected by the SLD detector at the SLC. The measurement benefits from the small and stable collision region at the SLC and the precision pixel vertex detector of the SLD. Three analysis techniques have been used: decay length, impact parameter, and impact parameter difference methods. The combined result is ${\mathrm{\ensuremath{\tau}}}_{\mathrm{\ensuremath{\tau}}}$=297\ifmmode\pm\else\textpm\fi{}9 (stat)\ifmmode\pm\else\textpm\fi{}5(syst) fs.