The anomalous dimension at the infrared fixed point of Nf = 12 SU(3) theory

We propose a novel renormalization scheme for the hadronic operators. As an example, we show the numerical simulation result for the anomalous dimension of the pseudo scalar operator of the SU(3) gauge theory coupled to Nf = 12 fundamental fermions. The anomalous dimension of the pseudo scalar operator is related with the mass renormalization factor of the fermion thought the partially conserved axial-vector current (PCAC) relation. We derive the mass anomalous dimension at the infrared fixed point (IRFP) of the theory, and find that it is given by gamma_m^*= 0.044_{-0.024}^{+0.025} (stat.)_{-0}^{+0.057} (syst.)_{-0.032}^{+0} (syst.), where the first systematic error comes from the uncertainty of the continuum extrapolation while the second one comes from the uncertainty of the value of the coupling constant at the IRFP.