Measurement of the Inclusive Electron Spectrum in Charmless Semileptonic B Decays Near the Kinematic Endpoint

The BABAR Collaboration; B. Aubert

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arXiv · hep-ex/0207081

Measurement of the Inclusive Electron Spectrum in Charmless Semileptonic B Decays Near the Kinematic Endpoint

The BABAR Collaboration·B. Aubert

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Abstract

A preliminary result on the study of the inclusive electron spectrum in B -> X_u e nu decays above the kinematic limit for the dominant B -> X_c e nu transitions is presented. This study is performed at the PEP-II asymmetric B Factory, where B meson pairs are produced in the decay of the Upsilon(4S) resonance. For the electron momentum range of 2.3 - 2.6 GeV/c in the Upsilon(4S) rest frame, the partial branching ratio is measured to be Delta B(B -> X_u e nu)=(0.152+-0.014+-0.014) 10^{-3}.

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The BABAR Collaboration, B. Aubert. 2002-07-25. Measurement of the Inclusive Electron Spectrum in Charmless Semileptonic B Decays Near the Kinematic Endpoint. https://arxiv.org/abs/hep-ex/0207081

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