Number of J/ψ events at BESIII *

Journal article

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.Comment: 6 pages, 2 figure

Authors: Ablikim, M; Achasov, MN; Adlarson, P; Ahmed, S; Albrecht, M

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: IOP Publishing
• Journal: Chinese Physics C
• Volume: 46
• Issue: 7
• Pages: 074001-074001
• Publication date: 2022-03-10
• DOI: 10.1088/1674-1137/ac5c2e
• ISSN: 1674-1137
• Language: English