Charmonium Spectrum from Quenched Lattice QCD with Tadpole\\ Improvement Action

We report our lattice simulation on the charmonium spectra in the quenched approximation. Because the complete adjustment on all the nonperturbative parameters needs much calculation time, we only adjust two of them, but with some rescaling for mass splitting. After the rescaling, the calculated masses of meson are 3.030GeV (ηc), 3.080GeV (J/ψ), 3.546GeV (hc) and 3.412 GeV (xc0) respectively, which is in agreement with the experimental results.