Hadron properties in lattice QCD with dynamical fermions

Incorporating dynamical Kogut-Susskind fermions into a Monte Carlo simulation of QCD, we have analyzed the masses of low-lying hadrons, chiral-symmetry breaking, and the interquark potential. We used a 24×123 lattice for two couplings g, where =6g2=5.20 and 5.35. The quark masses were ma=0.075, 0.050, and 0.025 (a being the lattice spacing). We find that the pattern of hadron masses of the , and N is qualitatively as seen experimentally. The pion mass squared is proportional to the quark mass and thus behaves as expected from chiral symmetry. Values for the quark condensate extrapolated to ma=0, the renormalization-group-invariant quark mass, and the pion decay constant are in reasonable agreement with values derived from experiment or from current algebra. If we fix the lattice spacing from the mass, we see evidence for the screening effect of light-quark-antiquark pairs in the potential between two massive quarks. At =5.20 and ma=0.050 we find good agreement between the results from our pseudofermion method and those from a hybrid simulation.