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arXiv · 1512.06987

Conserved Charge Fluctuations from Lattice QCD and the Beam Energy Scan

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

We discuss the next-to-leading order Taylor expansion of ratios of cumulants of net-baryon number fluctuations. We focus on the relation between the skewness ratio, $S_Bσ_B = χ_3^B/χ_1^B$, and the kurtosis ratio, $κ_Bσ_B^2 =χ_4^B/χ_2^B$. We show that differences in these two cumulant ratios are small for small values of the baryon chemical potential. The next-to-leading order correction to $κ_Bσ_B^2$ however is approximately three times larger than that for $S_Bσ_B$. The former thus drops much more rapidly with increasing beam energy, $\sqrt{s_{NN}}$. We argue that these generic patterns are consistent with current data on cumulants of net-proton number fluctuations measured by the STAR Collaboration at $\sqrt{s_{NN}}\ge 19.6$~GeV.

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F. Karsch, A. Bazavov, H. -T. Ding, P. Hegde, O. Kaczmarek, E. Laermann, Swagato Mukherjee, H. Ohno, P. Petreczky, C. Schmidt, S. Sharma, W. Soeldner, P. Steinbrecher, M. Wagner. 2015-12-22. Conserved Charge Fluctuations from Lattice QCD and the Beam Energy Scan. https://doi.org/10.1016/j.nuclphysa.2016.01.008

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