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arXiv · 1511.07447

Z' models for the LHCb and g-2 muon anomalies

Ben Allanach·Farinaldo S. Queiroz·Alessandro Strumia·Sichun Sun
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Abstract

We revisit a class of Z' explanations of the anomalies found by the LHCb collaboration in $B$ decays, and show that the scenario is tightly constrained by a combination of constraints: (i) LHC searches for di-muon resonances, (ii) pertubativity of the Z' couplings; (iii) the $B_s$ mass difference, and (iv) and electro-weak precision data. Solutions are found by suppressing the Z' coupling to electrons and to light quarks and/or by allowing for a Z' decay width into dark matter. We also present a simplified framework where a TeV-scale Z' gauge boson that couples to standard leptons as well as to new heavy vector-like leptons, can simultaneously accommodate the LHCb anomalies and the muon g-2 anomaly.

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Ben Allanach, Farinaldo S. Queiroz, Alessandro Strumia, Sichun Sun. 2015-11-23. Z' models for the LHCb and g-2 muon anomalies. https://doi.org/10.1103/physrevd.93.055045

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