Non-standard interactions in $τ^- \to (π^-η,π^-π^0)ν_τ$ decays

G. López Castro

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arXiv · 1812.05892

Non-standard interactions in $τ^- \to (π^-η,π^-π^0)ν_τ$ decays

G. López Castro

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Abstract

Originally thought as clean processes to study the hadronization of the weak currents, semileptonic tau lepton decays can be useful to set constraints on non-standard (NS) weak interactions. In this talk we summarize our recent studies on the effects of NS interactions in $τ^- \to (π^-π^0,π^-η)ν_τ$ decays. We find that experimental data on these decays provide strong constraints on NS scalar and tensor interactions, respectively. Further improved measurements at Belle II and a better knowledge of necessary tensor and scalar form factors will allow to set limits on these NS interactions that are similar or better to contraints obtained from other low-energy processes.

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BibTeX RIS

G. López Castro. 2018-12-14. Non-standard interactions in $τ^- \to (π^-η,π^-π^0)ν_τ$ decays. https://arxiv.org/abs/1812.05892

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