期刊论文

英文

中国科学：物理学、力学、天文学英文版

1674-7348

2023

66

02

28-37

supported by the National Key Research and Development Program of China （Grant Nos. 2020YFA0406400, and 2020YFA0406300）； Joint Large-Scale Scientific Facility Funds of the National Natural Science Foundation of China （NSFC） and Chinese Academy of Sciences （CAS） （Grant Nos. U1932101, U1732263, and U1832207）； State Key Laboratory of Nuclear Physics and Technology, Peking University （Grant No. NPT2020KFY04）； National Natural Science Foundation of China （Grant Nos. 11625523, 11635010, 11675275, 11735014, 11822506, 11835012, 11935015, 11935016, 11935018, 11961141012, 11975021, 12022510, 12035009, 12035013, 12061131003, and 12175321）； CAS Center for Excellence in Particle Physics （CCEPP）； CAS Large-Scale Scientific Facility Program； CAS Key Research Program of Frontier Sciences （Grant No. QYZDJSSW-SLH040）； 100 Talents Program of CAS, Fundamental Research Funds for the Central Universities, Institute of Nuclear and Particle Physics and Shanghai Key Laboratory for Particle Physics and Cosmology, European Research Council （Grant No. 758462）； European Union Horizon 2020 Research and Innovation Programme under Contract No. Marie SklodowskaCurie （Grant No. 894790）； German Research Foundation DFG （Grant No. 443159800）； Collaborative Research Center （Grant Nos. CRC 1044, FOR 2359, and GRK 2149）； Istituto Nazionale di Fisica Nucleare, Italy, Ministry of Development of Turkey （Grant No. DPT2006K-120470）； National Science and Technology fund, Olle Engkvist Foundation （Grant No. 200-0605）； Science and Technology Facilities Council （United Kingdom）； The Knut and Alice Wallenberg Foundation （Sweden） （Grant No. 2016.0157）； The Royal Society, UK （Grant Nos. DH140054, and DH160214）； The Swedish Research Council, U.S. Department of Energy （Grant Nos. DE-FG02-05ER41374, and DE-SC-0012069）； the IHEP computing center for their strong support；

本校为其他机构

We present a search for the lepton flavor violating decay J/ψ→e±μ?using 8.998 × 10~9J/ψ events collected with the BESⅢ detector at the BEPCⅡ e+e-storage ring.No excess of signal above background is observed;we therefore set an upper limit on the branching fraction of B（J/ψ→ e±μ?） ＜4.5 × 10-9 at the 90% confidence level.Improving the previous best result by a factor of more than 30,this measurement places the most stringent limit to date on le...