Measurement of J/ψ→ ηcγ at KEDR

We present a study of the inclusive photon spectra from 5.9 million J/ψ decays collected with the KEDR detector at the VEPP-4M e+e-collider.We measure the branching fraction of radiative decay J/ψ→ηcγ,ηc width and mass.Our preliminary results are: M(ηc)= 2979.4±1.5±1.9 MeV/c2,Г(ηc)=27.8±5.1±3.3 MeV,β(J/ψ→ηcγ)=(2.34±0.15±0.40)%.