Search for charged lepton flavor violation in $J/\psi$ decays at BESIII

Xudong Yu

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arXiv · 2405.00272

Search for charged lepton flavor violation in $J/\psi$ decays at BESIII

Xudong Yu

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Abstract

In the Standard Model, charged lepton flavor violation (CLFV) is heavily suppressed by tiny neutrino mass, while many theoretical models can enhance CLFV effects up to a detectable level. The observation of any CLFV process would be a clear signal of new physics beyond SM. BESIII experiment collected 10 billion $J/\psi$ data and searched for CLFV processes $J/\psi\to e\tau$ and $e\mu$. The upper limits at the 90% confidence level are determined to be $\mathcal{B}(J/\psi\to e\tau)<7.5\times 10^{-8}$ and $\mathcal{B}(J/\psi\to e\mu)<4.5\times 10^{-9}$, respectively. Improving the previously experimental limits by two orders of magnitudes, the results are the most stringent CLFV searches in the heavy quarkonium system.

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Xudong Yu. 2024-05-01. Search for charged lepton flavor violation in $J/\psi$ decays at BESIII. https://arxiv.org/abs/2405.00272

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