FINITE-SIZE EFFECT IN LATTICE QCD HADRON SPECTROSCOPY

A hadron spectrum calculation with two light dynamical quark flavors was carried out with the Kogut-Susskind quark action at beta = 5.7 on lattices of spatial size 8(3), 12(3), and 20(3) for m(q) = 0.01 and 0.02 in lattice units, with emphasis given to a systematic study of the finite-lattice-size effect. It is found that hadron masses on a 16(3) Spatial lattice at this beta still suffer from a significant finite-lattice effect at least for m(q) = 0.01, showing the importance of a quantitative control over the finite-size effect in comparing simulation results with the experimental hadron masses even for a fairly large lattice. A comparison is also made to the analytic prediction for the finite-size effect from chiral perturbation theory.