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arXiv · 1703.08170

Model-Independent Extraction of $|V_{cb}|$ from $\bar{B}\rightarrow D^* \ell \overline{\nu}$

Benjamin Grinstein·Andrew Kobach
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Abstract

We fit the unfolded data of $\bar{B}^0\rightarrow D^{*+} \ell \overline{\nu}$ from the Belle experiment, where $\ell \equiv e, \mu$, using a method independent of heavy quark symmetry to extrapolate to zero-recoil and extract the value of $|V_{cb}|$. This results in $|V_{cb}| = (41.9^{~+2.0}_{~-1.9})\times 10^{-3}$, which is robust to changes in the theoretical inputs and very consistent with the value extracted from inclusive semileptonic $B$ decays.

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Benjamin Grinstein, Andrew Kobach. 2017-03-23. Model-Independent Extraction of $|V_{cb}|$ from $\bar{B}\rightarrow D^* \ell \overline{\nu}$. https://doi.org/10.1016/j.physletb.2017.05.078

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