Precise Measurement of the Tau Lifetime

Abstract

The $\ensuremath{\tau}$ lifetime was measured with the Mark II vertex detector at the storage ring PEP. ${\ensuremath{\tau}}_{\ensuremath{\tau}}=(3.20\ifmmode\pm\else\textpm\fi{}0.41\ifmmode\pm\else\textpm\fi{}0.35)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}13}$ sec was found, which agrees well with $e\ensuremath{-}\ensuremath{\mu}\ensuremath{-}\ensuremath{\tau}$ university.