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|V_{ub}| From Semileptonic Decay and b -> s gamma

Adam K. Leibovich
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Abstract

Current errors on |V_{ub}| are dominated by model dependence. For inclusive decays, the model dependence comes from the Fermi motion of the b quark. By combining the endpoint photon and lepton spectra from the inclusive decays B -> X_s gamma and B -> X_u l nu, it is possible to remove this model dependence. We show how to combine these rates including the resummation of the endpoint logs at next to leading order. The theoretical errors on |V_{ub}| on the order of 10% are possible. We also give a brief discussion on comparing different extractions.

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Adam K. Leibovich. 2000-11-22. |V_{ub}| From Semileptonic Decay and b -> s gamma. https://arxiv.org/abs/hep-ph/0011181

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