D. Toussaint

Two-flavor staggered fermion thermodynamics at Nt = 12

We present results of an ongoing study of the nature of the high temperature crossover in QCD with two light fermion flavors. These results are obtained with the conventional staggered fermion action at the smallest lattice spacing to date, approximately 0.1 fm. Of particular interest are (1) a study of the temperature of the crossover, an important indicator of continuum scaling, (2) a determination of the induced baryon charge and baryon susceptibility, used to study the dissolution of hadrons at the crossover, (3) the scalar susceptibility, a signal for the appearance of soft modes, and (4) the chiral order parameter, used to test models of critical behavior associated with chiral symmetry restoration. From our new data and published results for

Thermodynamics of lattice QCD with two light quarks on a 16(3) x 8 lattice.

{N}_{t}=4, 6, mathrm{and} 8

Baryon Density Correlations in High Temperature Hadronic Matter

, we determine the QCD magnetic equation of state from the chiral order parameter using O(4) and mean field critical exponents and compare it with the corresponding equation of state obtained from an O(4) spin model and mean field theory. We also present a scaling analysis of the Polyakov loop, suggesting a temperature-dependent constituent quark free energy.

The deconfining phase transition in lattice quantum chromodynamics

We have extended our earlier simulations of the high temperature behaviour of lattice QCD with two light flavours of staggered quarks on a

Two-flavor staggered-fermion thermodynamics at Nt = 12

16^3 times 8

Hadronic screening lengths in the high-temperature plasma

lattice to lower quark mass (m_q=0.00625). The transition from hadronic matter to a quark-gluon plasma is observed at

Estimating the chiral-symmetry--restoration temperature in two-flavor QCD

6/g^2=5.49(2)

Chiral-symmetry breaking in lattice QCD with two and four fermion flavors.

corresponding to a temperature of

QCD thermodynamics with two flavors at Nt=6.

T_c approx 140

QCD thermodynamics with eight time slices

MeV. We present measurements of observables which probe the nature of the quark-gluon plasma and serve to distinguish it from hadronic matter. Although the transition is quite abrupt, we have seen no indications that it is first order.