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arXiv · 2109.14169

The sixth order cumulant of net-proton number in Binomial distribution at $\sqrt{s_{NN}} = $ 200 GeV

Li-Zhu Chen·Ye-Yin Zhao·Jin Wu·Zhi-Ming Li·Yuan-Fang Wu
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Abstract

It is proposed that ratios of the sixth order to the second order cumulant ($C_6/C_2$) of conserved quantities are sensitive to the chiral crossover transition. Recently, the negative $C_6/C_2$ was obtained both in theoretical Lattice QCD and experiments at $\sqrt{s_{NN}} = $ 200 GeV. In this study, we investigate the behavior of net-proton $C_6/C_2$ in statistical Binomial distribution (BD) at $\sqrt{s_{NN}} = $ 200 GeV in Au + Au collisions. With the BD parameters extracted from RHIC/STAR, it is found that $C_6/C_2$ can be negative. Furthermore, the obtained $C_6/C_2$ becomes smaller when applying the same magnitude of experimental statistics and calculation method to simulations. In 0-10\% centrality, there is a significant difference between the simulated result and theoretical expectation. Based on the extracted parameters and experimentally collected statistics, the baseline of net-proton $C_6/C_2$ in BD is presented.

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Li-Zhu Chen, Ye-Yin Zhao, Jin Wu, Zhi-Ming Li, Yuan-Fang Wu. 2021-09-29. The sixth order cumulant of net-proton number in Binomial distribution at $\sqrt{s_{NN}} = $ 200 GeV. https://doi.org/10.1088/1674-1137%2Fac1b98

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