Measurement of $B$-meson lifetimes using fully reconstructed $B$ decays produced in $p\overline{p}$ collisions at $\sqrt{s}=1.8\mathrm{}\hspace{0.5em}\mathrm{TeV}$

We present an improved measurement of b-meson lifetimes using fully reconstructed B-decays produced in $p\overline{p}$ collisions at $\sqrt{s}=1.8\mathrm{}\hspace{0.5em}\mathrm{TeV},$ using $114\hspace{0.5em}{\mathrm{pb}}^{-1}$ of data collected at the Collider Detector at Fermilab. We obtain $\tau {(B}^{+})=1.636\mathrm{}\pm 0.058(\mathrm{stat})\pm 0.025(\mathrm{syst})\hspace{0.5em}\mathrm{ps},$ $\tau {(B}^0)=1.497\mathrm{}\pm 0.073(\mathrm{stat})\pm 0.032(\mathrm{syst})\hspace{0.5em}\mathrm{ps}$ and for the lifetime ratio $\tau {(B}^{+})/\tau {(B}^0)=1.093\mathrm{}\pm 0.066\left(\mathrm{stat}\right)\pm 0.028\left(\mathrm{syst}\right).\mathrm{}$