Measurement of the Lifetime of Bottom Hadrons

The average lifetime of bottom hadrons was measured with the Mark II vertex detector at the storage ring PEP. The lifetime was determined by measuring the impact parameters of leptons produced in bottom decays. ${\ensuremath{\tau}}_{b}=({12.0}_{\ensuremath{-}3.6}^{+4.5}\ifmmode\pm\else\textpm\fi{}3.0)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}13}$ sec was found.