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arXiv · 2409.05588

CP violation in two-meson Tau decays induced by heavy new physics

Daniel A. López Aguilar·Javier Rendón·Pablo Roig
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Abstract

We apply the effective field theory formalism that was used to study CP violation induced by heavy new physics in the $τ\to K_S πν_τ$ decays to the other two-meson tau decay channels. We focus on the rate and the forward-backward asymmetries, that are predicted using current bounds on the complex Wilson coefficients of the effective Lagrangian. We discuss our outcomes for the modes with $(K/π)π^0$ and $K K_S$, that can be studied at Belle-II and a super-tau-charm facility. Our main finding is that current and forthcoming experiments would be sensitive to the maximum allowed CP rate asymmetry in the $K^\pm K_S$ modes if a precision of $5\%$ is reached on this observable, that can check as well the BaBar anomaly in $K_Sπ$. For the $π^\pmπ^0$ channels, new physics would be difficult to probe at present. Disentangling new sources of CP violation would be most challenging in $K^\pmπ^0$ and the other modes.

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Daniel A. López Aguilar, Javier Rendón, Pablo Roig. 2025-02-03. CP violation in two-meson Tau decays induced by heavy new physics. https://doi.org/10.1007/jhep01(2025)105

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