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Bottom-quark Fusion Processes at the LHC for Probing $Z^{prime}$ Models and B-meson Decay Anomalies

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 نشر من قبل Peisi Huang
 تاريخ النشر 2017
  مجال البحث
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We investigate models of a heavy neutral gauge boson Z which could explain anomalies in B meson decays reported by the LHCb experiment. In these models, the Z boson couples mostly to third generation fermions. We show that bottom quarks arising from gluon splitting can fuse into Z as an essential production mechanism at the LHC, thereby allowing to probe these models. The study is performed within a generic framework for explaining the B anomalies that can be accommodated in well motivated models. The flavor violating b s coupling associated with Z in such models produces lower bound on the production cross-section which gives rise to a cross-section range for such scenarios for the LHC to probe. Results are presented in Z -> $mu mu$ decays with at least one bottom-tagged jet in its final state. Some parts of the model parameter space become constrained by the existing dimuon-resonance searches by the ATLAS and CMS collaborations. However, the requirement of one or two additional bottom-tagged jets in the final state would allow for probing a larger region of the parameter space of the models at the ongoing LHC program.



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