Collider probe of heavy additional Higgs bosons solving the muon g-2 and dark matter problems

We study the Large Hadron Collider (LHC) search potential of a Z4-based two Higgs doublet model which can simultaneously explain the muon g - 2 anomaly and the observed dark matter. The neutral scalars in the second Higgs doublet couple to mu and tau and largely contribute to the muon anomalous magnetic moment through the one-loop diagram involving tau and scalars. An additional singlet scalar which is charged under the discrete symmetry can be a dark matter candidate. An upper limit on the scalar mass originates from the unitarity constraint, and the mu tau flavor-violating nature of the scalars predicts nonstandard signatures at the LHC. However, the previously proposed mu +/-mu +/-tau -/+tau -/+ signal via the electroweak heavy neutral scalar pair production at the LHC loses sensitivity for increasing scalar mass. We revisit this model and investigate the LHC prospects for the single production of the mu tau flavor-violating neutral scalar. It is shown that the single scalar process helps to extend the LHC reach to the 1 TeV mass regime of the scenario. The search potential at the high energy LHC is also discussed.

Automated summary

We studied the potential of the Large Hadron Collider (LHC) in searching for a Z4-based two Higgs doublet model that can explain both the muon g-2 anomaly and observed dark matter. The couplings between the neutral scalars in the second Higgs doublet and mu and tau strongly contribute to the muon anomalous magnetic moment. A charged singlet scalar, which is a candidate for dark matter, has an upper limit on its mass due to the unitarity constraint. The study revisits the model and explores the LHC prospects for the single production of the mu tau flavor-violating neutral scalar, extending the LHC reach to the 1 TeV mass regime.