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arXiv · 1703.09189

Status of the $B\to K^*μ^+μ^-$ anomaly after Moriond 2017

Wolfgang Altmannshofer·Christoph Niehoff·Peter Stangl·David M. Straub
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Abstract

Motivated by recent results by the ATLAS and CMS collaborations on the angular distribution of the $B \to K^* μ^+μ^-$ decay, we perform a state-of-the-art analysis of rare $B$ meson decays based on the $b \to s μμ$ transition. Using standard estimates of hadronic uncertainties, we confirm the presence of a sizable discrepancy between data and SM predictions. We do not find evidence for a $q^2$ or helicity dependence of the discrepancy. The data can be consistently described by new physics in the form of a four-fermion contact interaction $(\bar s γ_αP_L b)(\bar μγ^αμ)$. Assuming that the new physics affects decays with muons but not with electrons, we make predictions for a variety of theoretically clean observables sensitive to violation of lepton flavour universality.

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Wolfgang Altmannshofer, Christoph Niehoff, Peter Stangl, David M. Straub. 2017-06-02. Status of the $B\to K^*μ^+μ^-$ anomaly after Moriond 2017. https://doi.org/10.1140/epjc%2Fs10052-017-4952-0

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