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arXiv · 2507.10525

Novel and Updated Bounds on Flavor-Violating Z Interactions in the Quark Sector

Fayez Abu-Ajamieh·Amine Ahriche·Suman Kumbhakar·Nobuchika Okada
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Abstract

We derive bounds on the flavor-violating (FV) couplings of the $Z$ boson to quarks and present future sensitivity projections. Our analysis shows that the current bounds on the FV couplings are $\mathcal{O}(10^{-9})$ for the $Z$ couplings to $cu$ and $sd$, $\mathcal{O}(10^{-7})$ for $bd$, $\mathcal{O}(10^{-6})$ for $bs$, and $\mathcal{O}(10^{-3})$ for $tu$ and $tc$. Overall, low-energy flavor experiments provide significantly stronger constraints on these FV couplings than current collider searches.

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Fayez Abu-Ajamieh, Amine Ahriche, Suman Kumbhakar, Nobuchika Okada. 2025-07-14. Novel and Updated Bounds on Flavor-Violating Z Interactions in the Quark Sector. https://doi.org/10.1142/s0217751x26500569

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