Search for the Lepton Flavour Violating decays $\Upsilon(2S)\rightarrow e^{\pm}\mu^{\mp}$ and $\Upsilon(3S)\rightarrow e^{\pm}\mu^{\mp}$

H. Ahmed; N. Tasneem; J. M. Roney

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arXiv · 2603.05799

Search for the Lepton Flavour Violating decays $\Upsilon(2S)\rightarrow e^{\pm}\mu^{\mp}$ and $\Upsilon(3S)\rightarrow e^{\pm}\mu^{\mp}$

H. Ahmed·N. Tasneem·J. M. Roney

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Abstract

Charged lepton flavour violating processes are unobservable in the standard model, but they are predicted to be enhanced in several new physics extensions. We present the results of a search for $\Upsilon (2S)$ and $\Upsilon (3S)$ decays to $e^{\pm}\mu^{\mp}$ decays. The search was conducted using data samples consisting of 99 million $\Upsilon (2S)$ and 122 million $\Upsilon (3S)$ mesons, collected at center-of-mass energies of 10.02 and 10.36 GeV, respectively, by the BABAR detector at the SLAC PEP-II $e^{+}e^{-}$ collider.

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H. Ahmed, N. Tasneem, J. M. Roney. 2026-03-06. Search for the Lepton Flavour Violating decays $\Upsilon(2S)\rightarrow e^{\pm}\mu^{\mp}$ and $\Upsilon(3S)\rightarrow e^{\pm}\mu^{\mp}$. https://arxiv.org/abs/2603.05799

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