Highly Enhanced Contributions of Heavy Higgs Bosons and New Leptons to Muon g-2 and Prospects at Future Colliders.

Radovan Dermisek,Navin Mcginnis,Keith Hermanek

doi:10.1103/physrevlett.126.191801

Radovan Dermisek, Navin Mcginnis + Show 1 more

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https://doi.org/10.1103/physrevlett.126.191801

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Abstract

We show that, in a two Higgs doublet model type II extended by vectorlike leptons, the contributions from heavy neutral and charged Higgs bosons to the anomalous magnetic moment of the muon simultaneously feature chiral enhancement from masses of new leptons and tan^{2}β enhancement from couplings of Higgs bosons. Assuming moderate values of new Yukawa couplings, not exceeding one, that can remain perturbative to very high energy scales, the measured value of muon g-2 can be explained within one standard deviation even with 6.5TeV leptons or 20TeV Higgs bosons. Allowing new couplings near the perturbativity limit, these mass ranges extend to 45TeV for leptons and 185TeV for Higgs bosons. In spite of the high scale of new physics, this scenario can be completely probed at planned future colliders.

Highlights

Introduction.—The discrepancy between the measured value of the muon anomalous magnetic moment ðg − 2Þμ and the standard model (SM) prediction, one of the largest discrepancies among precision electroweak (EW) measurements, is of the same order as the contributions of Z and W bosons
Well-known examples include the enhancement by the ratio of vacuum expectation values of the two Higgs doublets, tan β, in supersymmetric models [5] and chiral enhancement in models with vectorlike leptons [6,7]
In this Letter, we show that in a two Higgs doublet model type II (2HDM-II), which is one of the simplest and most studied extensions of the SM Higgs sector [12], with vectorlike leptons mixing with the muon, there are contributions to ðg − 2Þμ originating from heavy neutral CPeven (H), CP-odd (A), and charged Higgs (HÆ) bosons and new leptons which, in addition to chiral enhancement from masses of new leptons, are enhanced by tan2 β compared to contributions of W, Z, and h bosons and new leptons

Summary

Introduction

Introduction.—The discrepancy between the measured value of the muon anomalous magnetic moment ðg − 2Þμ and the standard model (SM) prediction, one of the largest discrepancies among precision electroweak (EW) measurements, is of the same order as the contributions of Z and W bosons. As a result of this enhancement, we show that the measured value of ðg − 2Þμ can be explained within one standard deviation even with 6.5 TeV leptons or 20 TeV Higgs bosons, assuming moderate values of all new Yukawa couplings not exceeding one, which can remain perturbative to very high energy scales, possibly the grand unification scale (depending on other details of the mopdffieffiffilffi)ffi.

Results

Conclusion