Heavy quark potentials in quenched QCD at high temperature - art. no. 034021

Heavy quark potentials are investigated at high temperatures. The temperatu re range covered by the analysis extends from T values just below the decon finement temperature up to about 4T(c) in the deconfined phase. We simulate d the pure gauge sector of QCD on lattices with temporal extents of 4, 6, a nd 8, with spatial volumes of 32(3). On the smallest lattice a tree level i mproved action was employed, while in the other two cases the standard Wils on action was used. Below T-c we find a temperature-dependent logarithmic t erm contributing to the confinement potential, and observe a string tension which decreases with rising temperature but retains a finite value at the deconfinement transition. Above T-c the potential is Debye screened; howeve r, simple perturbative predictions do not apply.