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arXiv · 2008.11909

Muon Anomalous Magnetic Moment in Two Higgs Doublet Models with Vector-Like Leptons

Abstract

We show that inclusion of a single generation of vector-like leptons in the Two-Higgs Doublet Models significantly enlarges the allowed parameter space consistent with the muon anomalous magnetic moment, as well as with other theoretical and experimental constraints. While previously $(g -2)_\mu$ could only be resolved in Type-X scenario by requiring a light pseudoscalar Higgs boson and large $\tan \beta$, contributions of vector-like leptons via two-loop Barr Zee diagrams broaden the allowed parameter space, allowing $\tan \beta$ as low as 10 and pseudoscalar masses as large as $\cal{O}$(1 TeV) while fulfilling the stringent constraints from precision and flavor observable. Similar results are obtained for Type-II scenarios, but there the parameter space is more restricted by flavor observables.

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BibTeXRIS

Mariana Frank, Ipsita Saha. 2020-08-27. Muon Anomalous Magnetic Moment in Two Higgs Doublet Models with Vector-Like Leptons. https://doi.org/10.1103/physrevd.102.115034

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