Measurement of the time dependence of Bd0 ↔ Bd0 mixing using leptons and D∗± mesons

doi:10.1016/0370-2693(94)90577-0

Physics Letters B

Volume 336, Issues 3–4, 29 September 1994, Pages 585-598

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Abstract

Data collected with the OPAL detector at LEP during 1990–1993 are used to measure the time dependence of $B_{d}^{0} ↔ B_{d}^{0}$ mixing. From a sample of 153 ± 12 events with a charged D^∗ and a lepton in the opposite hemisphere, we measure the $B_{d}^{0} ↔ B_{d}^{0}$ oscillation frequency to be Δm_d = 0.57±0.11(stat.)±0.02(syst.) ps⁻¹. This corresponds to an oscillation parameter of x_d = Δm_dτ_B_d⁰ = 0.82±0.16(stat.) ± 0.03(syst.) ± 0.09(syst. τ_{B⁰_d}), where the second systematic uncertainty is due to the error in the measured B_d⁰ lifetime.

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¹: Also at TRIUMF, Vancouver, Canada V6T 2A3.

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Physics Letters B

Abstract

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Review of B<sup>0</sup> - B<sup>0</sup> oscillation measurements

Limit on B<sup>0</sup><inf>s</inf> oscillation using a jet charge method

B mesons