Abstract
Direct CP asymmetry in semi-leptonic τ decays is an intriguing hint for new physics beyond the standard model. We investigate the CP asymmetry in \( {\tau}^{-}\to {K}_S^0{\pi}^{-}{\nu}_{\tau } \) and τ− → K−π0ντ decays in the context of the non-minimal SU(5) model, with 45-dimensional Higgs multiplet. We show that the associate color-triplet scalar, which is a natural example of a scalar leptoquark, can mediate the \( \tau \to s\overline{u}{\nu}_{\tau } \) transition and account for the observed 2.8 σ discrepancy in \( {A}_{\textrm{CP}}\left({\tau}^{-}\to {K}_S^0{\pi}^{-}{\nu}_{\tau}\right) \) compared to the SM expectation. We also predict a sizable ACP(τ− → K−π0ντ), of \( \mathcal{O} \)(10−3), which can be experimentally accessible in current and near future experiments.
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The work of S. K. is partially supported by Science, Technology & Innovation Funding Authority (STDF) under grant number 37272.
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Faisel, G., Khalil, S. CP asymmetry in τ → Kπντ within non-minimal SU(5). J. High Energ. Phys. 2023, 99 (2023). https://doi.org/10.1007/JHEP05(2023)099
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DOI: https://doi.org/10.1007/JHEP05(2023)099