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arXiv · 0812.2795

|Vub| from Exclusive Semileptonic B--> rho Decays

Jonathan M Flynn·Yoshiyuki Nakagawa·Juan Nieves·Hiroshi Toki
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Abstract

We use Omnes representations of the form factors V, A_1 and A_2 for exclusive semileptonic B--> rho decays, and apply them to combine experimental partial branching fraction information with theoretical calculations of the three form factors to extract |Vub|. We find a slightly lower result, |Vub|=(2.8 +- 0.2)x 10^{-3}, than the values extracted from exclusive semileptonic B-->pi decays and using all other inputs in CKM fits. The disagreement is greater when we compare to the result extracted from inclusive B -> X_u l nu decays.

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Jonathan M Flynn, Yoshiyuki Nakagawa, Juan Nieves, Hiroshi Toki. 2008-12-15. |Vub| from Exclusive Semileptonic B--> rho Decays. https://doi.org/10.1016/j.physletb.2009.04.037

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