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arXiv · hep-ex/9406004

Semileptonic Branching Fraction of Charged and Neutral B Mesons

The CLEO collaboration
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Abstract

An examination of leptons in ${Υ(4S)}$ events tagged by reconstructed $B$ decays yields semileptonic branching fractions of $b_-=(10.1 \pm 1.8\pm 1.4)\%$ for charged and $b_0=(10.9 \pm 0.7\pm 1.1)\%$ for neutral $B$ mesons. This is the first measurement for charged $B$. Assuming equality of the charged and neutral semileptonic widths, the ratio $b_-/b_0=0.93 \pm 0.18 \pm 0.12$ is equivalent to the ratio of lifetimes. A postscript version is available through World-Wide-Web in http://w4.lns.cornell.edu/public/CLNS/1994

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The CLEO collaboration. 1994-06-23. Semileptonic Branching Fraction of Charged and Neutral B Mesons. https://doi.org/10.1103/physrevlett.73.3503

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