Measurement of the {ital B}{sup +} and {ital B}{sup 0} Lifetimes Using Topological Reconstruction of Inclusive and Semileptonic Decays

The lifetimes of B{sup +} and B{sup 0} mesons are measured using a sample of 150000hadronic Z{sup 0} decays collected by the SLD experiment at the SLAC Linear Collider between 1993 and 1995. Two analyses are presented in which the decay length and charge of the {ital B} meson are reconstructed. The first method uses a novel topological vertexing technique while the second uses semi-inclusively reconstructed semileptonic decays. The topological analysis yields a sample of 6033 (3665) charged (neutral) vertices with good charge purity, whereas the semileptonic analysis yields a smaller sample of 634 (584) charged (neutral) decays with excellent charge purity. Combining the results from both analyses, we find {tau}{sub B{sup +}}=1.66{plus_minus}0.06(stat ){plus_minus}0.05(syst) ps, {tau}{sub B{sup 0}}=1.64{plus_minus}0.08(stat ){plus_minus}0.08(syst) ps, and {tau}{sub B{sup +}}/{tau}{sub B{sup 0}} =1.01{plus_minus}0.07(stat){plus_minus}0.06( syst) . {copyright} {ital 1997} {ital The American Physical Society}