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arXiv · 1707.07016

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

Abstract

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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Mohammad Abdullah, Mykhailo Dalchenko, Bhaskar Dutta, Ricardo Eusebi, Peisi Huang, Teruki Kamon, Denis Rathjens, Adrian Thompson. 2017-07-21. Bottom-quark Fusion Processes at the LHC for Probing $Z^{\prime}$ Models and B-meson Decay Anomalies. https://doi.org/10.1103/physrevd.97.075035

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