The OPAL Collaboration, K. Ackerstaff et al
Published 1998-01-31Version 1
This paper presents updated measurements of the lifetimes of the B^0_s meson and the \Lambda_b baryon using 4.4 million hadronic Z^0 decays recorded by the OPAL detector at LEP from 1990 to 1995. A sample of B^0_s decays is obtained using D_s^- \ell^+ combinations, where the D_s^- is fully reconstructed in the \phi \pi^-, K^*0 K^- and K^- K^0_S decay channels and partially reconstructed in the \phi \ell^- \nu(bar) X decay mode. A sample of \Lambda_b decays is obtained using \Lambda_c^+ \ell^- combinations, where the \Lambda_c^+ is fully reconstructed in its decay to a p K^- \pi^+ final state and partially reconstructed in the \Lambda \ell^+ \nu X decay channel. From 172 +/- 28 D_s^- \ell^+ combinations attributed to B^0_s decays, the measured lifetime is \tau(B^0_s) = 1.50 +0.16 -0.15 +/- 0.04 ps, where the errors are statistical and systematic, respectively. From the 129 +\- 25 \Lamda_c^+ \ell^- combinations attributed to \Lambda_b decays, the measured lifetime \tau(\Lambda_b) = 1.29 +0.24 -0.22 +/- 0.06 ps, where the errors are statistical and systematic, respectively.
Comments: 21 pages, LaTeX, uses a4p.sty, 4 eps figures included, submitted to Phys. Lett. B
Journal: Phys.Lett.B426:161-179,1998
Measurements of the relative branching fractions of the $B^{+} \to p \bar p K^{+}$ decay channel including charmonium contributions
Measurements of the Ratios ${\cal B}(D_s^+\to η\ell^+ν)/{\cal B}(D_s^+\to φ\ell^+ν)$ and ${\cal B}(D_s^+\to η'\ell^+ν)/{\cal B}(D_s^+\to φ\ell^+ν)$
Observation of a resonance in the K$_s$p decay channel at a mass of 1765 MeV/c$^2$
