Lattice thermodynamics at finite chemical potential from analytical Continuation

Abstract

An efficient way to study the QCD phase diagram at small finite density is to extrapolate thermodynamical observables from imaginary chemical potential. We present results for fluctuations of baryon number to order (μB/T)6. The results at real chemical potentials are obtained through analytical continuation of simulations at imaginary chemical potentials. We also calculate higher order fluctuations of strangeness and electric charge to obtain the Taylor coefficients of the baryon number fluctuation with vanishing strangeness. We compare to the STAR proton fluctuation data to characterize the chemical freeze-out in view of the lattice results.