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arXiv · hep-ex/0208033

Measurement of the inclusive semileptonic branching fraction of B mesons and |Vcb|

The Belle collaboration
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Abstract

We present a measurement of the electron spectrum from inclusive semileptonic {\it B} decay, using 5.1 fb$^{-1}$ of $Υ(4S)$ data collected with the Belle detector. A high-momentum lepton tag was used to separate the semileptonic {\it B} decay electrons from secondary decay electrons. We obtained the branching fraction, ${\cal B}(B\to X e^+ ν) = (10.90 \pm 0.12 \pm 0.49)%$, with minimal model dependence. From this measurement, we derive a value for the Cabibbo-Kobayashi-Maskawa matrix element $|V_{cb}| = 0.0408 \pm 0.0010 {\rm (exp)} \pm 0.0025{\rm (th)}$.

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The Belle collaboration. 2002-08-20. Measurement of the inclusive semileptonic branching fraction of B mesons and |Vcb|. https://doi.org/10.1016/s0370-2693(02)02770-3

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