Measurement of theD0,D+, andDs+meson lifetimes

We report measurements of the lifetimes of the ${D}^{0}$, ${D}^{+}$, and ${D}_{s}^{+}$ (${F}^{+}$) mesons produced in ${e}^{+}$${e}^{\mathrm{\ensuremath{-}}}$ collisions at a center-of-mass energy of 29 GeV. The decay vertex distributions in the processes ${D}^{0}$\ensuremath{\rightarrow}${K}^{\mathrm{\ensuremath{-}}}$${\ensuremath{\pi}}^{+}$, ${D}^{+}$\ensuremath{\rightarrow}${K}^{\mathrm{\ensuremath{-}}}$${\ensuremath{\pi}}^{+}$${\ensuremath{\pi}}^{+}$, and ${D}_{s}^{+}$\ensuremath{\rightarrow}\ensuremath{\varphi}${\ensuremath{\pi}}^{+}$ were made using a vertex chamber installed in the High Resolution Spectrometer at the SLAC storage ring PEP. The measured lifetimes are =(4.4\ifmmode\pm\else\textpm\fi{}1.0\ifmmode\pm\else\textpm\fi{}0.6)\ifmmode\times\else\texttimes\fi{}${10}^{\mathrm{\ensuremath{-}}13}$ s, ${=(9.2}_{\mathrm{\ensuremath{-}}1.3}^{+1.7}$\ifmmode\pm\else\textpm\fi{} 1.6)\ifmmode\times\else\texttimes\fi{}${10}^{\mathrm{\ensuremath{-}}13}$ s, and ${=(3.1}_{\mathrm{\ensuremath{-}}2.0}^{+2.4}$\ifmmode\pm\else\textpm\fi{}0.5) \ifmmode\times\else\texttimes\fi{}${10}^{\mathrm{\ensuremath{-}}13}$ s. In addition the lifetime of the ${B}^{0}$ meson is determined assuming that only the ${B}^{0}$ and not the ${B}^{\mathrm{\ensuremath{-}}}$ decays to a ${D}^{\mathrm{*}+}$ meson. The ${B}^{0}$ is not directly observed. The lifetime is estimated indirectly to be ${(8.2}_{\mathrm{\ensuremath{-}}3.7}^{+5.7}$\ifmmode\pm\else\textpm\fi{}2.7) \ifmmode\times\else\texttimes\fi{}${10}^{\mathrm{\ensuremath{-}}13}$ s.