Lepton flavor-changing Scalar Interactions and Muon $g-2$

Abstract

A systematic investigation on muon anomalous magnetic moment and related lepton flavor-violating process such as $\m\to e\g$, $\t\to e\g$ and $\t\to \m\g$ is made at two loop level in the models with flavor-changing scalar interactions. The two loop diagrams with double scalar exchanges are studied and their contributions are found to be compatible with the ones from Barr-Zee diagram. By comparing with the latest data, the allowed ranges for the relevant Yukawa couplings $Y_{ij}$ in lepton sector are obtained. The results show a hierarchical structure of $Y_{\m e, \t e} \ll Y_{\m \t} \simeq Y_{\m\m}$ in the physical basis if $\Delta a_{\mu }$ is found to be $>50\times 10^{-11}$. It deviates from the widely used ansatz in which the off diagonal elements are proportional to the square root of the products of related fermion masses. An alternative Yukawa coupling matrix in the lepton sector is suggested to understand the current data. With such a reasonable Yukawa coupling ansatz, the decay rate of $\t\to \m\g$ is found to be near the current experiment upper bound.

15 pages, Revtex, 9 figures, published version in EPJC

Cited by in corpus (17)

• Long-Lived Particles at the Energy Frontier: The MATHUSLA Physics Case
• New physics explanations of $a_{\mu }$ in light of the FNAL muon $g-2$ measurement
• A light complex scalar for the electron and muon anomalous magnetic moments
• Lepton flavour violating Higgs and tau to mu gamma
• Mass matrix Ansatz and lepton flavor violation in the THDM-III
• Detecting Hidden Particles with MATHUSLA
• A joint explanation of W-mass and muon g-2 in 2HDM
• Two-Higgs doublet solution to the LSND, MiniBooNE and muon $g-2$ anomalies
• The Tiny (g-2) Muon Wobble from Small-$\mu$ Supersymmetry
• A Light Scalar Explanation of $(g-2{)}_{\mu }$ and the KOTO Anomaly
• Two-Higgs-doublet models in light of current experiments: a brief review
• A Call for New Physics : The Muon Anomalous Magnetic Moment and Lepton Flavor Violation
• Texture of Yukawa coupling matrices in general two-Higgs-doublet model
• CP asymmetry in $B\to \varphi K_S$ in a general two-Higgs-doublet model with fourth-generation quarks
• Using atomic clocks to detect local dark matter halos
• Probing Type-I 2HDM light Higgs in the top-pair-associated diphoton channel
• Unitarity bounds on extensions of Higgs sector