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arXiv · 1710.09817

$\overline{B}\rightarrow D^\ast\ell\overline{\nu}$ at non-zero recoil

A. Vaquero Avilés-Casco·C. DeTar·D. Du·A. El-Khadra·A. S. Kronfeld·J. Laiho·R. S. Van de Water
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Abstract

We present preliminary results from our analysis of the form factors for the $\overline{B}\rightarrow D^\ast\ell\overline{\nu}$ decay at non-zero recoil. Our analysis includes 15 MILC asqtad ensembles with $N_f=2+1$ flavors of sea quarks and lattice spacings ranging from $a\approx 0.15$ fm down to $0.045$ fm. The valence light quarks employ the asqtad action, whereas the heavy quarks are treated using the Fermilab action. We conclude with a discussion of future plans and phenomenological implications. When combined with experimental measurements of the decay rate, our calculation will enable a determination of the CKM matrix element $|V_{cb}|$.

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A. Vaquero Avilés-Casco, C. DeTar, D. Du, A. El-Khadra, A. S. Kronfeld, J. Laiho, R. S. Van de Water. 2017-10-26. $\overline{B}\rightarrow D^\ast\ell\overline{\nu}$ at non-zero recoil. https://arxiv.org/abs/1710.09817

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