Measurement of Γee(J/ψ)⋠B(J/ψ→e+e−) and Γee(J/ψ)⋠B(J/ψ→μ+μ−)

Assuming eμ universality and using the world average value of the lepton branching fraction, we also determine the leptonic Γℓℓ=5.59±0.12 keV and total Γ=94.1±2.7 keV widths of the J/ψ meson.