Searching for lepton flavor violation processes at BES

In this paper, the recent results of searching for lepton flavor violation process via the decays J/ψ→eμ, J/ψ→μτ, τ→eν¯eντ and J/ψ→eτ, τ→μν¯μντ using 5.8×107J/ψ events collected with the BESII detector [J.Z. Bai, et al., BBS Collab., Nucl. Instr. Meth. A 458, 627 (2001)] are reported. Four, zero and one candidate events, consistent with the estimated background, are observed in J/ψ→eμ, J/ψ→μτ, τ→eν¯eντ and J/ψ→eτ, τ→μν¯μντ decays, respectively. Upper limits on the branching ratios are determined to be Br(J/ψ→eμ)<1.1×10−6, Br(J/ψ→μτ)<2.0×10−6 and Br(J/ψ→eτ)<8.3×10−6 at the 90% confidence level.