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arXiv · 2207.12420

Semi-inclusive Lepton Flavor Universality ratio in $b\to s\ell^+\ell^-$ transitions

Marco Ardu·Gino Isidori·Marko Pesut
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Abstract

We construct a semi-inclusive Lepton Flavour Universality (LFU) ratio, $R_\Sigma$, to test $\mu/e$ universality in $b\to s\ell^+\ell^-$ transitions at $e^+e^-$ $B$-meson factories. Combining different decay channels, this observable maximises the sensitivity to possible LFU violations of short distance origin, yet preserving a clean theoretical interpretation in case of a deviation from its Standard Model prediction, $R_\Sigma^{\rm SM}=1$.

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Marco Ardu, Gino Isidori, Marko Pesut. 2022-07-25. Semi-inclusive Lepton Flavor Universality ratio in $b\to s\ell^+\ell^-$ transitions. https://doi.org/10.1103/physrevd.106.093008

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