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arXiv · hep-ex/0601027

Experimental Limits on Weak Annihilation Contributions to b -->u ell nu Decay

J. L Rosner·CLEO Collaboration
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Abstract

We present the first experimental limits on high-q^2 contributions to charmless semileptonic B decays of the form expected from the Weak Annihilation (WA) decay mechanism. Such contributions could bias determinations of |Vub| from inclusive measurements of B-> X_u lnu. Using a wide range of models based on available theoretical input we set a limit of (Gamma_WA/Gamma_b->u) < 7.4% (90% confidence level) on the WA fraction, and assess the impact on previous inclusive determinations of |Vub|.

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J. L Rosner, CLEO Collaboration. 2006-01-16. Experimental Limits on Weak Annihilation Contributions to b -->u ell nu Decay. https://doi.org/10.1103/physrevlett.96.121801

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