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arXiv · 1912.05886

The \boldmath$B\to D^\ast\ell\nu$ semileptonic decay at nonzero recoil and its implications for $\ |V_{cb}\ |$ and $R(D^\ast)$

Alejandro Vaquero Avilés-Casco·Carleton DeTar·Aida X. El-Khadra·Andreas S. Kronfeld·Jack Laiho·Ruth S. Van de Water
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Abstract

We present nearly final results from our analysis of the form factors for $B\to D^\ast\ell\nu$ decay at nonzero recoil. Our analysis includes 15 MILC asqtad ensembles with $N_f=2+1$ flavors of sea quarks and lattice spacings ranging from $a\approx0.15$ fm down to $0.045$ fm. The valence light quarks employ the asqtad action, whereas the $b$ and $c$ quarks are treated using the Fermilab action. We discuss the impact that our results will have on $\ |V_{cb}\ |$ and $R(D^\ast)$.

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Alejandro Vaquero Avilés-Casco, Carleton DeTar, Aida X. El-Khadra, Andreas S. Kronfeld, Jack Laiho, Ruth S. Van de Water. 2019-12-12. The \boldmath$B\to D^\ast\ell\nu$ semileptonic decay at nonzero recoil and its implications for $\ |V_{cb}\ |$ and $R(D^\ast)$. https://arxiv.org/abs/1912.05886

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