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arXiv · 1712.05802

Bottom-quark Forward-Backward Asymmetry, Dark Matter and the LHC

Da Liu·Jia Liu·Carlos E. M. Wagner·Xiao-Ping Wang
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Abstract

The LEP experiment at CERN provided accurate measurements of the $Z$ neutral gauge boson properties. Although all measurements agree well with the SM predictions, the forward backward asymmetry of the bottom-quark remains almost 3$\sigma$ away from the SM value. We proposed that this anomaly may be explained by the existence of a new $U(1)_D$ gauge boson, which couples with opposite charges to the right-handed components of the bottom and charm quarks. Cancellation of gauge anomalies demands the presence of a vector-like singlet charged lepton as well as a neutral Dirac (or Majorana) particle that provides a Dark Matter candidate. Constraints from precision measurements imply that the mass of the new gauge boson should be around $115$~GeV. We discuss the experimental constraints on this scenario, including the existence of a di-jet resonance excess at an invariant mass similar to the mass of this new gauge boson, observed in boosted topologies at the CMS experiment.

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Da Liu, Jia Liu, Carlos E. M. Wagner, Xiao-Ping Wang. 2017-12-15. Bottom-quark Forward-Backward Asymmetry, Dark Matter and the LHC. https://doi.org/10.1103/physrevd.97.055021

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