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arXiv · 0911.2399

Study of $B\to K^{(*)} \ell^+\ell^-$ Decays in the Family Non-universal $Z'$ Models

Cheng-Wei Chiang·Run-Hui Li·Cai-Dian Lü
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Abstract

In a combined investigation of the $B\to K^{(*)}\ell^+\ell^-$ decays, constraints on the related couplings in family non-universal $Z^{\prime}$ models are derived. We find that within the allowed parameter space, the recently observed forward-backward asymmetry in the $B\to K^*\ell^+\ell^-$ decay can be explained, by flipping the signs of the Wilson coefficients $C_9^{\rm eff}$ and $C_{10}$. With the obtained constraints, we also calculate the branching ratio of the $B_s\to\mu^+\mu^-$ decay. The upper bound of our prediction is near the upper bound given by CDF Collaboration recently.

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Cheng-Wei Chiang, Run-Hui Li, Cai-Dian Lü. 2009-11-12. Study of $B\to K^{(*)} \ell^+\ell^-$ Decays in the Family Non-universal $Z'$ Models. https://doi.org/10.1088/1674-1137/36/1/003

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