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arXiv · 1605.07633

On the Standard Model predictions for $R_K$ and $R_{K^*}$

Marzia Bordone·Gino Isidori·Andrea Pattori
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Abstract

We evaluate the impact of radiative corrections in the ratios $Γ[B\to M μ^+μ^-]/Γ[B\to M e^+e^-]$ when the meson $M$ is a $K$ or a $K^*$. Employing the cuts on $m^2_{\ell\ell}$ and the reconstructed $B$-meson mass presently applied by the LHCb Collaboration, such corrections do not exceed a few $\%$. Moreover, their effect is well described (and corrected for) by existing Montecarlo codes. Our analysis reinforces the interest of these observables as clean probe of physics beyond the Standard Model.

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Marzia Bordone, Gino Isidori, Andrea Pattori. 2017-05-05. On the Standard Model predictions for $R_K$ and $R_{K^*}$. https://doi.org/10.1140/epjc%2Fs10052-016-4274-7

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