Dispersive theory of charmonium on the Lattice

Physical contribution of the high-energy part of hadronic spectrum is incorporated to describe the short-distance part of the correlator of heavy-quark currents obtained by quenched Monte-Carlo on a $8^3*16$- and $16^3*32$-lattices for $\beta= \{ 6, 6.3 \}$. The lattice artifacts in the short-distance behavior of that correlator are isolated. The physical short-distance part of the correlator is fitted by the relevant expressions of perturbative QCD, which allows one to obtain the renormalized charmed quark mass with rather high accuracy $m_c^{\bar{MS}}(m_c)\,=\,1.22(5)\,GeV$.