QCD thermodynamics in the crossover/freeze-out region

We use results from a 6-th order Taylor expansion of the QCD equation of state to construct expansions for cumulants of conserved charge fluctuations and their correlations. We show that these cumulants strongly constrain the range of applicability of hadron resonance gas model calculations. We point out that the latter is inappropriate to describe equilibrium properties of QCD at zero and non-zero values of the baryon chemical potential already at T~155 MeV.

Comments: 5 pages, 6 figures, contribution to the International Conference "Critical Point and Onset of Deconfinement 2016", Wroc{\l}aw, Poland, May 30th - June 4th, 2016

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