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arXiv · 1607.04857

Explanation of $B \to K^{(*)} \ell^+ \ell^-$ and muon $g-2$, and implications at the LHC

Abstract

More than $3\sigma$ deviations from the standard model are observed in the angular observable $P'_5$ of $B\to K^* \mu^+ \mu^-$ and muon $g-2$. To resolve these anomalies, we extend the standard model by adding two leptoquarks. It is found that the signal strength of the diphoton Higgs decay can exhibit a significant deviation from unity and is within the data errors. Although $\ell_i \to \ell_j \gamma$ puts severe bounds on some couplings, it is found that the excesses of $P'_5$ and muon $g-2$ can still be explained and can be accommodated to the measurement of $B_s\to \mu^+ \mu^-$ in this model. In addition, the leptoquark effects can also explain the LHCb measurement of $R_K = BR(B^+ \to K^+ \mu^+\mu^-)/BR(B^+ \to K^+ e^+e^-)=0.745^{+0.090}_{-0.074} \pm 0.036$, which shows a $2.6\sigma$ deviation from the standard model prediction.

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Chuan-Hung Chen, Takaaki Nomura, Hiroshi Okada. 2016-07-17. Explanation of $B \to K^{(*)} \ell^+ \ell^-$ and muon $g-2$, and implications at the LHC. https://doi.org/10.1103/physrevd.94.115005

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