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arXiv · 1509.05786

The curvature of the freeze-out line in heavy ion collisions

A. Bazavov·H. -T. Ding·P. Hegde·O. Kaczmarek·F. Karsch·E. Laermann·Swagato Mukherjee·H. Ohno·P. Petreczky·C. Schmidt·S. Sharma·W. Soeldner·M. Wagner
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Abstract

We calculate the mean and variance of net-baryon number and net-electric charge distributions from Quantum Chromodynamics (QCD) using a next-to-leading order Taylor expansion in terms of temperature and chemical potentials. We compare these expansions with experimental data from STAR and PHENIX, determine the freeze-out temperature in the limit of vanishing baryon chemical potential, and, for the first time, constrain the curvature of the freeze-out line through a direct comparison between experimental data on net-charge fluctuations and a QCD calculation. We obtain a bound on the curvature coefficient, kappa_2^f < 0.011, that is compatible with lattice QCD results on the curvature of the QCD transition line.

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A. Bazavov, H. -T. Ding, P. Hegde, O. Kaczmarek, F. Karsch, E. Laermann, Swagato Mukherjee, H. Ohno, P. Petreczky, C. Schmidt, S. Sharma, W. Soeldner, M. Wagner. 2016-02-05. The curvature of the freeze-out line in heavy ion collisions. https://doi.org/10.1103/physrevd.93.014512

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