Using a data sample of 448.1×106 ψ(3686) events collected at s=3.686 GeV with the BESIII detector at the Beijing Electron-Positron Collider II, we search for the rare decay J/ψ→φe+e- via ψ(3686)→π+π-J/ψ. No signal events are observed and the upper limit on the branching fraction is set to be B(J/ψ→φe+e-)<1.2×10-7 at the 90% confidence level, which is still about one order of magnitude higher than the Standard Model prediction.
Bibliographical noteFunding Information:
The BESIII Collaboration thanks the staff of BEPCII and the IHEP computing center for their strong support. This work is supported in part by National Key Basic Research Program of China under Contract No. 2015CB856700; National Natural Science Foundation of China (NSFC) under Contracts No. 11575077, No. 11475090, No. 11235011, No. 11335008, No. 11425524, No. 11625523, No. 11635010, No. 11735014, and No. 11835012; the Natural Science Foundation of Hunan Province under Contract No. 2019JJ30019; the Chinese Academy of Sciences (CAS) Large-Scale Scientific Facility Program; Joint Large-Scale Scientific Facility Funds of the NSFC and CAS under Contracts No. U1532257, No. U1532258, No. U1732263, and No. U1832207; CAS Key Research Program of Frontier Sciences under Contracts No. QYZDJ-SSW-SLH003 and No. QYZDJ-SSW-SLH040; 100 Talents Program of CAS; INPAC and Shanghai Key Laboratory for Particle Physics and Cosmology; German Research Foundation DFG under Collaborative Research Center Contract No. CRC 1044; Istituto Nazionale di Fisica Nucleare, Italy; Koninklijke Nederlandse Akademie van Wetenschappen (KNAW) under Contract No. 530-4CDP03; Ministry of Development of Turkey under Contract No. DPT2006K-120470; National Science and Technology fund; The Knut and Alice Wallenberg Foundation (Sweden) under Contract No. 2016.0157; The Swedish Research Council; U.S. Department of Energy under Contracts No. DE-FG02-05ER41374, No. DE-SC-0010118, and No. DE-SC-0012069; University of Groningen (RuG) and the Helmholtzzentrum für Schwerionenforschung GmbH (GSI), Darmstadt.
© 2019 authors. Published by the American Physical Society.