A. Bazavov

Equation of state and QCD transition at finite temperature

We calculate the equation of state in

Freeze-out Conditions in Heavy Ion Collisions from QCD Thermodynamics

2+1

Scaling studies of QCD with the dynamical highly improved staggered quark action

flavor QCD at finite temperature with physical strange quark mass and almost physical light quark masses using lattices with temporal extent

Strangeness at high temperatures: from hadrons to quarks

{N}_{ensuremath{tau}}=8

The chiral transition and

. Calculations have been performed with two different improved staggered fermion actions, the asqtad and p4 actions. Overall, we find good agreement between results obtained with these two

U(1)_A

O({a}^{2})

symmetry restoration from lattice QCD using Domain Wall Fermions

improved staggered fermion discretization schemes. A comparison with earlier calculations on coarser lattices is performed to quantify systematic errors in current studies of the equation of state. We also present results for observables that are sensitive to deconfining and chiral aspects of the QCD transition on

Deconfinement and chiral transition with the highly improved staggered quark (HISQ) action

{N}_{ensuremath{tau}}=6

Refining New-Physics Searches inB→Dτνwith Lattice QCD

and 8 lattices. We find that deconfinement and chiral symmetry restoration happen in the same narrow temperature interval. In an appendix we present a simple parametrization of the equation of state that can easily be used in hydrodynamic model calculations. In this parametrization we include an estimate of current uncertainties in the lattice calculations which arise from cutoff and quark mass effects.

MILC results for light pseudoscalars

We present a determination of freeze-out conditions in heavy ion collisions based on ratios of cumulants of net electric charge fluctuations. These ratios can reliably be calculated in lattice QCD for a wide range of chemical potential values by using a next-to-leading order Taylor series expansion around the limit of vanishing baryon, electric charge and strangeness chemical potentials. From a computation of up to fourth order cumulants and charge correlations we first determine the strangeness and electric charge chemical potentials that characterize freeze-out conditions in a heavy ion collision and confirm that in the temperature range 150 MeV ≤ T ≤ 170 MeV the hadron resonance gas model provides good approximations for these parameters that agree with QCD calculations on the 5%-15% level. We then show that a comparison of lattice QCD results for ratios of up to third order cumulants of electric charge fluctuations with experimental results allows us to extract the freeze-out baryon chemical potential and the freeze-out temperature.