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Muon Anomalous Magnetic Moment, Two-Higgs-Doublet Model, and Supersymmetry

Kingman Cheung·Chung-Hsien Chou·Otto C. W. Kong
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Abstract

The recent measurement on the muon anomalous magnetic moment $a_μ$ shows a $2.6σ$ deviation from the standard model value. We show that it puts strong constraints on the parameter space of the two-higgs doublet model (2HDM) II. The dominant contribution of the Higgses comes at the two-loop level, and in order to explain the data it favors a pseudoscalar $A$ with a light mass range and a large $\tanβ$. At 95% C.L., upper limit for $m_{\scriptscriptstyle A}$ is $29 (55) (85)$ GeV for $\tanβ=30 (45) (60)$, and $\tan β$ is bounded below at 17. This is in sharp contrast to the conclusion one draws from considering one-loop Higgs contributions alone. Finally, we also discuss the role of the Higgs contributions in the minimal supersymmetric standard model.

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Kingman Cheung, Chung-Hsien Chou, Otto C. W. Kong. 2001-10-05. Muon Anomalous Magnetic Moment, Two-Higgs-Doublet Model, and Supersymmetry. https://doi.org/10.1103/physrevd.64.111301

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