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Measurement of the Relative Branching Fraction of $Υ(4S)$ to Charged and Neutral B-Meson Pairs

J. P. Alexander·CLEO Collaboration
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Abstract

We analyze 9.7 x 10^6 B\bar{B}$ pairs recorded with the CLEO detector to determine the production ratio of charged to neutral B-meson pairs produced at the Y(4S) resonance. We measure the rates for B^0 -> J/psi K^{(*)0} and B^+ -> J/psi K^{(*)+} decays and use the world-average B-meson lifetime ratio to extract the relative widths f+-/f00 = Gamma(Y(4S) -> B+B-)/Gamma(Y(4S) -> B0\bar{B0}) = = 1.04 +/- 0.07(stat) +/- 0.04(syst). With the assumption that f+- + f00 = 1, we obtain f00 = 0.49 +/- 0.02(stat) +/- 0.01(syst) and f+- = 0.51 +/- 0.02(stat) +/- 0.01(syst). This production ratio and its uncertainty apply to all exclusive B-meson branching fractions measured at the Y(4S) resonance.

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J. P. Alexander, CLEO Collaboration. 2000-06-08. Measurement of the Relative Branching Fraction of $Υ(4S)$ to Charged and Neutral B-Meson Pairs. https://doi.org/10.1103/physrevlett.86.2737

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