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Can $B -> X_c \ell ν$ help us extract |V_{ub}| ?

H. Boos·Th. Feldmann·T. Mannel·B. D. Pecjak
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Abstract

We study radiative corrections to $\bar{B} \to X_c \ell \barν_\ell$ decays assuming the power counting $m_c \sim \sqrt{Λ_QCD m_b}$ for the charm-quark mass. Concentrating on the shape-function region, we use effective field-theory methods to calculate the hadronic tensor at NLO accuracy. From this we deduce a shape-function independent relation between partially integrated $\bar{B} \to X_c\ell\barν_\ell$ and $\bar{B} \to X_u \ell \barν_\ell$ spectra to leading power in $1/m_b$, including first-order corrections in the strong coupling constant. This may provide an independent cross-check on the determination of the CKM element |V_{ub}|.

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H. Boos, Th. Feldmann, T. Mannel, B. D. Pecjak. 2006-05-04. Can $B -> X_c \ell ν$ help us extract |V_{ub}| ?. https://doi.org/10.1088/1126-6708%2F2006%2F05%2F056

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