SCALING STUDY OF PURE GAUGE LATTICE QCD BY MONTE-CARLO RENORMALIZATION-GROUP METHOD

The scaling behavior of pure gauge SU(3) in the region beta = 5.85-7.6 0 is examined by a Monte Carlo renormalization group analysis. The cou pling shifts induced by factor 2 blocking are measured on both 32(4) a nd 16(4) lattices with high statistics. A systematic deviation from na ive 2-loop scaling is clearly seen. The mean field and effective coupl ing constant schemes explain part, but not all, of the deviation. It c an be accounted for by a suitable change of coupling constant, includi ng a correction term O(g7) in the 2-loop lattice beta function. Based on this improvement, square-root sigma/LAMBDA(MS)/n(f)=0 is estimated to be 2.2 +/- 0.1 from the analysis of the string tension sigma.