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τ^- \to μ^- π^0(η,η') Decays in New Physics Scenarios beyond the Standard Model

Wenjun Li·Yadong Yang·Xiangdan Zhang
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Abstract

The semileptonic decays $τ^- \to μ^- M (M=π^0,η,η')$ could be sensitive probe for new physics scenarios with lepton flavor violation(LFV). Motivated by the recent Belle measurement, we investigate these decays in type III two-Higgs-doublet model (2HDM III), R-parity violating supersymmetric models(RPV SUSY) and flavor changing $Z'$ models with family non-universal couplings, respectively. In these new physics scenarios, there are LFV couplings at tree level. Our results have shown that the decays are very sensitive to the LFV couplings and could be enhanced to the present experimental sensitivities. We have derived strong bounds on relevant couplings of these models, which may be useful for further relevant studies.

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Wenjun Li, Yadong Yang, Xiangdan Zhang. 2006-02-22. τ^- \to μ^- π^0(η,η') Decays in New Physics Scenarios beyond the Standard Model. https://doi.org/10.1103/physrevd.73.073005

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