Author/Authors :
OPAL Collaboration، نويسنده , , K Ackerstaff، نويسنده , , G Alexander، نويسنده , , J Allison، نويسنده , , N. Altekamp، نويسنده , , K.J. Anderson، نويسنده , , S Anderson، نويسنده , , S Arcelli، نويسنده , , S Asai، نويسنده , , S.F Ashby، نويسنده , , D Axen، نويسنده , , G Azuelos، نويسنده , , A.H. Ball، نويسنده , , E Barberio، نويسنده , , R.J. Barlow، نويسنده , , R. Bartoldus، نويسنده , , J.R. Batley، نويسنده , , S Baumann، نويسنده , , J Bechtluft، نويسنده , , C Beeston، نويسنده , , et al.، نويسنده ,
Abstract :
This paper presents updated measurements of the lifetimes of the Bs0 meson and the Λb0 baryon using 4.4 million hadronic Z0 decays recorded by the OPAL detector at LEP from 1990 to 1995. A sample of Bs0 decays is obtained using Ds−ℓ+ combinations, where the Ds− is fully reconstructed in the φπ−, K∗0K− and K−K0S decay channels and partially reconstructed in the φℓ−ν̄X decay mode. A sample of Λb0 decays is obtained using Λc+ℓ− combinations, where the Λc+ is fully reconstructed in its decay to a pK−π+ final state and partially reconstructed in the Λℓ+νX decay channel. From 172±28 Ds−ℓ+ combinations attributed to Bs0 decays, the measured lifetime is τ(Bs0)=1.50+0.16−0.15±0.04 ps, where the errors are statistical and systematic, respectively. From the 129±25 Λc+ℓ− combinations attributed to Λb0 decays, the measured lifetime is τ(Λb0)=1.29+0.24−0.22±0.06 ps, where the errors are statistical and systematic, respectively.