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arXiv · hep-ex/9811018

Search for B0s oscillations using inclusive lepton events

ALEPH collaboration
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Abstract

A search for B0s oscillations is performed using a sample of semileptonic b-hadron decays collected by the ALEPH experiment during 1991-1995. Compared to previous inclusive lepton analyses, the proper time resolution and b-flavour mistag rate are significantly improved. Additional sensitivity to B0s mixing is obtained by identifying subsamples of events having a B0s purity which is higher than the average for the whole data sample. Unbinned maximum likelihood amplitude fits are performed to derive a lower limit of Deltam_s>9.5ps^-1 at 95% CL. Combining with the ALEPH D-s based analyses yields Deltam_s>9.6ps^-1 at 95% CL.

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ALEPH collaboration. 1998-11-11. Search for B0s oscillations using inclusive lepton events. https://doi.org/10.1007/s100529901108

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