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arXiv · 1703.06124

A fresh look at the determination of |V_cb| from B-> D^* l nu

Dante Bigi·Paolo Gambino·Stefan Schacht
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Abstract

We use recent Belle results on $\bar{B}^0\rightarrow D^{*+}l^-\barν_l$ decays to extract the CKM element $|V_{cb}|$ with two different but well-founded parameterizations of the form factors. We show that the CLN and BGL parameterizations lead to quite different results for $|V_{cb}|$ and provide a simple explanation of this unexpected behaviour. A long lasting discrepancy between the inclusive and exclusive determinations of $|V_{cb}|$ may have to be thoroughly reconsidered.

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Dante Bigi, Paolo Gambino, Stefan Schacht. 2017-04-26. A fresh look at the determination of |V_cb| from B-> D^* l nu. https://doi.org/10.1016/j.physletb.2017.04.022

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