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arXiv · 2204.10783

Search for the charged-lepton-flavor-violating decay $Z\rightarrow e\mu$ in $pp$ collisions at $\sqrt{s}=13$ TeV with the ATLAS detector

ATLAS Collaboration
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Abstract

A search for the charged-lepton-flavor-violating process $Z\rightarrow e\mu$ is presented, using 139 fb$^{-1}$ of $\sqrt{s}=13$ TeV $pp$ collision data collected by the ATLAS experiment at the LHC. An excess in the $e\mu$ invariant mass spectrum near the $Z$ boson mass would be a striking signature of new physics. No excess is observed, and an upper limit $B(Z\rightarrow e\mu) < 2.62 \times 10^{-7}$ is placed on the branching fraction at 95% confidence level, which is the most stringent limit to date.

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ATLAS Collaboration. 2022-04-22. Search for the charged-lepton-flavor-violating decay $Z\rightarrow e\mu$ in $pp$ collisions at $\sqrt{s}=13$ TeV with the ATLAS detector. https://doi.org/10.1103/physrevd.108.032015

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