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arXiv · hep-ex/9707010

An Updated Study of B Meson Oscillations using Dilepton Events

The OPAL Collaboration·K. Ackerstaff et al
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Abstract

This paper reports a study of B meson oscillations using hadronic Z^0 decays with two identified leptons, and updates a previous publication by including data collected in 1994. Decay times are reconstructed for each of the semileptonic B decays by forming vertices which include the lepton and by estimating the B meson momentum. The mass difference, Delta(m_d), between the two mass eigenstates in the B^0_d system is measured to be 0.430 +/- 0.043 + 0.028 - 0.030 ps^-1, where the first error is statistical and the second error is systematic. For the B^0_s system, a lower limit of Delta(m_s) > 2.2 ps^-1 is obtained at 95% C.L.

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The OPAL Collaboration, K. Ackerstaff et al. 1997-07-03. An Updated Study of B Meson Oscillations using Dilepton Events. https://doi.org/10.1007/s002880050565

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