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Collider constraints on Z models for neutral current B-anomalies

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We examine current collider constraints on some simple Z models that fit neutral current B-anomalies, including constraints coming from measurements of Standard Model (SM) signatures at the LHC. The ‘MDM’ simplified model is not constrained by the SM measurements but is strongly constrained by a 139 fb−1 13 TeV ATLAS di-muon search. Constraints upon the ‘MUM’ simplified model are much weaker. A combination of the current Bs mixing constraint and ATLAS’ Z search implies \( {M}_{Z^{\prime }}>1.2 \) TeV in the Third Family Hypercharge Model example case. LHC SM measurements rule out a portion of the parameter space of the model for \( {M}_{Z^{\prime }}>1.5 \) TeV.


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Allanach, B.C., Butterworth, J.M. & Corbett, T. Collider constraints on Z models for neutral current B-anomalies. J. High Energ. Phys. 2019, 106 (2019).

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  • Beyond Standard Model
  • Heavy Quark Physics