Lattice Study on Tensor Glueball in Radiative $J/\psi$ Decay

The radiative decay of $J/\psi$ into a pure gauge tensor glueball is studied in the quenched lattice QCD formalism. With two anisotropic lattices, the mutlipole amplitudes E_1(0), M_2(0) and E_3(0) are obtained to be 0.114(12)GeV, -0.011(5)GeV} and 0.023(8)GeV, respectively. Thus the partial decay width $\Gamma(J/\psi\rightarrow \gamma G_{2^{++}})$ is estimated to be 0.99(22)keV which corresponds to a large branch ratio 1.1(2)x10^{-2}. The phenomenological implication of this result is also discussed.