2024/05/01 by Yu, Xudong
#FOS: Physical sciences #High Energy Physics - Experiment (hep-ex)
paper · doi:10.48550/arxiv.2405.00272
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/ψ data and searched for CLFV processes J/ψ→ eτ and eμ. The upper limits at the 90% confidence level are determined to be B(J/ψ→ eτ)<7.5× 10-8 and B(J/ψ→ eμ)<4.5× 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.