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تسجيل مستخدم جديدConserved Charge Fluctuations from Lattice QCD and the Beam Energy Scan
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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, $S_Bsigma_B = chi_3^B/chi_1^B$, and the kurtosis ratio, $kappa_Bsigma_B^2 =chi_4^B/chi_2^B$. 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 $kappa_Bsigma_B^2$ however is approximately three times larger than that for $S_Bsigma_B$. 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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