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arXiv · 1903.02100

Semi-leptonic form factors for $B_s \to K \ell \nu$ and $B_s \to D_s \ell \nu$

Jonathan M. Flynn·Ryan C. Hill·Andreas Jüttner·Amarjit Soni·Justus Tobias Tsang·Oliver Witzel
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Abstract

Semi-leptonic $B_s \to K \ell \nu$ and $B_s \to D_s \ell \nu$ decays provide an alternative $b$-decay channel to determine the CKM matrix elements $|V_{ub}|$ and $|V_{cb}|$ or to obtain $R$-ratios to investigate lepton flavor universality violations. In addition, these decays may shed further light on the discrepancies seen in the analysis of inclusive vs. exclusive decays. Using the nonperturbative methods of lattice QCD, theoretical results are obtained with good precision and full control over systematic uncertainties. This talk will highlight ongoing efforts of the $B$-physics program by the RBC-UKQCD collaboration.

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Jonathan M. Flynn, Ryan C. Hill, Andreas Jüttner, Amarjit Soni, Justus Tobias Tsang, Oliver Witzel. 2019-03-05. Semi-leptonic form factors for $B_s \to K \ell \nu$ and $B_s \to D_s \ell \nu$. https://arxiv.org/abs/1903.02100

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