QCD with dynamical Wilson fermions—First results from SESAM

Abstract

First results of a recently started simulation of full QCD with two flavours of sea-quarks at a coupling of β = 5.6 on a 163 × 32 lattice are presented. Emphasis is laid on the statistical significance that can be achieved by an “integrated luminosity” of 140 TFlop×hrs, for Hybrid Monte Carlo simulations at four intermediate values of mπmρ. The simulation takes place on the Quadrics QH2 at DESY/Zeuthen and DFG/Bielefeld. The performance is optimized by means of BiCGStab and the chronological inversion method of Brower et al. We discuss the systematic errors arising from lack of the molecular dynamic's reversibility on the 32-bit QH2. For plaquette and meson correlators we find integrated autocorrelation times of < 20 units of molecular dynamics time and exponential autocorrelation times of about 50 units. Using these results we perform preliminary measurements of the central potential and π and ρ correlators on independent configurations and obtain first estimates of the lattice spacings at three values of the dynamical hopping parameter.