A search for the charged lepton flavor violating decay J/ψ→e±τ with τ →π π0ντ is performed with about 10×109 J/ψ events collected with the BESIII detector at the BEPCII. No significant signal is observed, and an upper limit is set on the branching fraction B(J/ψ→e±τ)<7.5×10-8 at the 90% confidence level. This improves the previously published limit by two orders of magnitude.
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- 1.03 ФИЗИЧЕСКИЕ НАУКИ И АСТРОНОМИЯ