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arXiv · 0808.0011

Evidence for B semileptonic decays into the charmed baryon Lambda_c+

The BABAR Collaboration·B. Aubert
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Abstract

We present the first evidence for B semileptonic decays into the charmed baryon Lambda_c+ based on 420 fb-1 of data collected at the Upsilon(4S) resonance with the BABAR detector at the PEP-II e+e- storage rings. Events are tagged by fully reconstructing one of the B mesons in a hadronic decay mode. We measure the relative branching fraction BF(Bbar -> Lambda_c+ X l- nubar_l)/BF(Bbar -> Lambda_c+/Lambda_c- X) = (3.2 +/- 0.9_stat +/- 0.9_syst)%. The significance of the signal including the systematic uncertainty is 4.9 standard deviations.

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The BABAR Collaboration, B. Aubert. 2008-07-31. Evidence for B semileptonic decays into the charmed baryon Lambda_c+. https://arxiv.org/abs/0808.0011

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