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arXiv · 1601.04277

Continuum limit of the leading order HQET form factor in $B_s \to K\ell\nu$ decays

Felix Bahr·Debasish Banerjee·Fabio Bernardoni·Anosh Joseph·Mateusz Koren·Hubert Simma·Rainer Sommer
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Abstract

We discuss the computation of form factors for semi-leptonic decays of $\rm B$-, $\rm B_s$- mesons in lattice QCD. Considering in particular the example of the static $\rm B_s$ form factors we demonstrate that after non-perturbative renormalization the continuum limit can be taken with confidence. The resulting precision is of interest for extractions of $V_{\rm ub}$. The size of the corrections of order $1/m_{\rm b}$ is just estimated at present but it is expected that their inclusion does not pose significant difficulties.

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Felix Bahr, Debasish Banerjee, Fabio Bernardoni, Anosh Joseph, Mateusz Koren, Hubert Simma, Rainer Sommer. 2016-01-17. Continuum limit of the leading order HQET form factor in $B_s \to K\ell\nu$ decays. https://doi.org/10.1016/j.physletb.2016.03.088

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